My wife and I had our first baby a month ago. She prefers to pump a few bottles worth of milk at a time and feed the baby from the bottle. She stores the bottles in the fridge.

My little brother has never had a girlfriend. He acts quite awkward around my wife and other women from what I've seen. He came to my house last week to see the baby and he noticed the bottles in the fridge.

Yesterday, my wife and I, along with our baby, went over to my parent's house. My brother knows since he's in our family group chat. He texted me when I was at my parent's house that he bought my baby some cool clothes and will drop them off. He knows my front door pin to get in.

When I got home I saw the cool clothes he bought and thanked him via text. My wife bottle fed my baby that night with no issues. Today, however, she said the baby reacted very differently to the new bottle she fed her. She coughed much more than usual and spat out the milk, which never happened before. So, my wife tasted it and said it was cow milk, not her milk. She told me to taste it too and compare it with the two other bottles in the fridge. That bottle indeed tasted much more like cow milk than the other two.

My wife suspected it was my brother drinking her breast milk and swapping out that bottle with cow milk. I agreed that it would not be out of character for him to do that. I thought it was a bit fishy he would come by and drop off clothes, especially since that was the first time he would come to my house when no one was home.

I called my brother and asked him why he would drop by when we were not home and why he couldn't wait a few hours until we got home. He said he just bought the clothes from the nearby mall and it was more convenient to drop them off then. I asked him to please tell me the truth if he swapped my wife's breast milk with cow milk and he vehemently denied it. I told him how we found out the bottle contained cow milk and what a coincidence it must be. He said he really doesn't know, but I could hear the tremble in his words. I told him that my wife and I don't believe him and if he doesn't apologize now, we would tell our parents what happened and ask what they think. He once again denies doing anything so I hung up.

Before calling my parents, I want to know what you guys think first. Are my wife and I just paranoid or do we have good enough reason to believe my brother swapped out her breast milk with cow milk? u/902I0

Not Around my Kids!

Wow this is weird.... does he have a history of this kind of thing? It almost seems sexually deviant. Why would he do this? Breastmilk is usually a bit different in color then cow milk, more yellow, much sweeter, and cows milk is definitely way harder for babies to digest. So if you are sure it was cow milk in the bottle, then it sounds like he's the only one that could have done it. Anyone else in your house? Maybe ask him in person. Face to face. To be sure. If he did this, then he was putting your baby's health at risk for his own twisted gain, and that is really crappy of him. I wouldn't want him around my kids! Raven3131

Mistakes Happen....

Did you even think about the possibility that he just knocked it over? That he was smelling and looking and dropped it. Or that he has this awful rash and has read breastmilk helps (true) and used it for that. You mind jumps right to drinking, but that's not at all the issue.

Cows milk is very, very bad for baby's. They should not be drinking it at all. I would tell your brother that, make it clear why it's bad and ask him if he, or anyone else, can be honest next time something happens to the breastmilk. If it falls, be honest, do NOT replace with cow's milk. Or with anything.

Also, how did she not notice? They don't look the same at all. It's really barely a mistake you can make, unless you don't look at the bottle when you take it out of the fridge. Gwennie333

Check Up. 

My daughter got really really sick (she was hospitalized) from drinking cow's milk. And she is 5 months old so I can only imagine how much more dangerous it is to a month-old. I'm not in the best position to give my judgement. Mine is to urge you to please follow up and check if everything is okay with your baby. murrayxi

Be Sure. 

You sound somewhat skeptical that it was 100% cow milk— If it was cow milk, it was surely your brother. In which case; NTA at all. Cow milk is not good, and can mess some babies up digestion-wise. NTA, and your brother is weird. jakejames

I don't have the best of taste buds. Plus, the temperature of the supposed cow milk is a bit warmer than the refrigerated breast milk, so that throws things off a little. I'm 90% sure it's cow milk and my wife said she's 100% sure. 902I0

Skin Crawl.

I am a breastfeeding mom, and this made my skin crawl. If it really was drank by him, how absolutely intrusive and deviant. It's very dangerous for babies to have anything other then formula/breastmilk when they're that young as well..

The only other explanation I can think of is the milk going bad somehow. Which if you're freezing before 24 hours it shouldn't be bad and should be fine in the fridge.

Your brother is a creep if he did that, and I would keep him away from your wife and baby. Dontsuffocate

"you just know?"

INFO

WTH is this thread? Everybody either on the crap post train or NTA bandwagon??

OP, do you have any (I mean any) actual evidence that he did something wrong? None of those intuition nonsense or "you just know?".. that's not gonna cut it. Especially if you're planning on some sort of grand spectacle where you make your brother appear like some creepy sexual pervert.

Maybe take a step back, deep breath and think whether whatever evidence you have is enough/conclusive because your relationship with your brother will likely never be the same afterwards but surely you wouldn't want to be on the wrong side of that discussion?

EDIT: Because it seems many responses are tripping up on this.. "none of this intuition nonsense" refers to the brother having done something and not whether it was or wasn't breast milk. That's a separate discussion in itself. rycology

Not in this House. 

NTA, and maybe make sure he cant get into your house when you're not home. That can be terrible for the poor baby's digestion, even deadly depending on the age. And... it sounds like your brother might be a sexual deviant, if he has done this, then he has gone out of his way to set up a situation where he's violating your wife's dignity in her own home. Protect your family from the threat, brother or not, and tell your parents. Cow milk and breast milk are noticeably different, trust your judgement and make sure these more subtle offenses don't turn into something more sinister. Your wife must feel pretty gross, I'm sorry for you both. haveitoldyouyethaveitoldyouyet

Sour taste.

NTA, him drinking your wife's milk is incredibly creepy, and not only that but he also endangered your child's health. If I was your wife I wouldn't want him near me, breastfeeding a child is extremely personal, him inserting himself into that feels really intrusive and wrong. nessy612

About Him. 

Has he ever done anything comparable to this that would lead you to believe it was him? I mean the evidence you have is pretty damning as it is. casualpotato96

Nothing comparable. He's a socially awkward but very intelligent guy. He never got into trouble as a kid. But like I said, he's super awkward around women, so I wouldn't be surprised if he's a bit sexually deviant. 902I0

Menace. 

NTA, and the really serious issue here is that your baby could have been killed by his stunt. Google infants drinking cow's milk. Change your pin code. Your brother is a menace and a weirdo. I wouldn't ever trust him again. Take your baby to the doctor immediately and tell them what happened. brotogeris1

Accidents Happen.

I really hope the dude like dropped or accidentally used them or something. But i'd feel like he would admit if that happened so. Korpela

I'm sorry to tell you this because it's disgusting but there are a fair amount of men who drink breast milk because they think it will help them gain muscle mass.

Edit: okay I get that it's not actually that disgusting and just bc something grosses me out doesn't mean it's automatically bad. I do think it's stupid because there is 0% proof that it works and also a lot of the time they're buying it out while parents whose babies can't take formula and whose mothers can't provide enough for them really struggle (my cousin went through this) so I don't have a lot of respect for the guys involved lmao. hogelett

Get Him!

Nail his butt to the wall. There is a huge difference between the sweet taste of breast milk and cow milk. Newborns can't digest cow milk, can have a bad reaction to it, and your baby could have gotten really sick from drinking it. Even before formula and if another nursing mom couldn't help they never gave babies straight cow milk. Goat milk is much closer to human milk. Your brother might of just been curious but he has to know you don't mess with the baby's stuff because they can get hurt. lisasimpsonfan

"will you go fill up a bottle of milk for my baby?" 

Don't ever underestimate people's ability to be ignorant of things you think are obvious. This is the same world where men thought there were left and right tampons. I don't know anything about babies (I'm a woman) and if I hadn't seen various PETA things about how cows milk isn't meant for humans, I might not realize that it made much difference. I could see someone saying "will you go fill up a bottle of milk for my baby?" and grabbing the quart of cows milk without realizing they were supposed to look for a bottle that had been pumped. I once had a friend who couldn't figure out that you had to put water in a coffee maker in addition to the grounds. Smart guy, too, at least in terms of book intelligence. JLLsat

Set a Trap....

This might be horrible advice, but I would tell your brother that the baby is having a horrible reaction to the milk and is in the ER and you need to know if the baby drank cow milk.

Edit: I have been enjoying the conversation this comment has turned out, thanks for that and the silver.

In reality, OP most likely already missed his chance at a straight out confession and doing this tactic wouldn't work if the brother is already on the defensive.

I do think it is fair game to say the baby is having a reaction and it is important to know if the milk was changed. Maybe he could have framed it as something where he thought the brother was trying to do a favor and filled a bottle for them, that they appreciate it, but if it is cow's milk, it is bad for the baby... etc. etc. Punky_Grifter

Is He a Fool?

Is your brother an adult? What the hell is he doing swapping out food for your child like that, and drinking breast milk? I tell you the code to my place would be changed immediately. What else has he done in your place? MaryK007

He's 23. I will definitely change my code ASAP. He hasn't done anything out of the ordinary in my place since he's only there when I'm home as far as I know. u/902I0

Get a new Code... 

I'd make sure to not give him the new code. Cows milk is not good for babies under 1yr. As a pumping mother the taste between breast milk and cows milk is very different, there is no way you could mistake the taste. It may have been curiosity or, as others have said, if he is a body builder he may have heard it's good for muscle repair or he might have decided to try and sell some. But in my opinion he has drunk it. I would test the other bottles or even dispose of them rather than feed them to your baby, in case he has tampered with them too. Kapearce82

Family Can be Trouble. 

I read the other comments before making this post. Specifically to the other folks saying this couldn't be real... I hate to be the one to point this out, but lactation fetishes are real, and quite common.

OP, follow the other poster's advice. Change your security PIN, limit your brother's access to your wife and child, and tell your parents about this breach of trust. You need to make it clear to your brother that his behavior hurt his family and it's unacceptable.

Also, tell your wife to look through her undergarments to see if anything is missing. While I don't want to condemn your brother as "the creepy pervert" I wouldn't be surprised if she was missing at least one pair of undergarments. CIA_astroturf_acct82

HIDE! 

You're not an a**hole.

Bro what the HECK??? I don't think you should let your brother see your wife anymore cause that's so creepy. I know I'd be mad about it. I'm not sure how your relationship with ur brother is but I'd definitely distance myself. He's a creep and a fool in my opinion, especially if he DRANK it. I cannot even begin to imagine how uncomfortable and upset you and your wife are, but I hope things turn out well and that you guys get some peace of mind. Sara-tonin-

Be Serious.

Seriously, this needs to be on top! OP just had a baby a mouth ago. A child this young should not be having cow's milk this young since their digestion system isn't fully develop and can't digest it fully.

Cow's Milk vs. Formula

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