Good friends are the ones you can always rely on when times are tough. For Selma Blair that person has been her long time friend Sarah Michelle Gellar.
The actresses grew close while filming Cruel Intentions back in 1999 and have been besties ever since their days as "Kathryn" and "Cecile".
On Thursday the pair took to Instagram to celebrate their 20 year long friendship with a couple of heartwarming messages to each other.
"This girl. (Always my girl) is everything." Blair wrote. "She tucked me in and brought me dinner and loved me up. I woke with so much love for #sarahmichellegellar."
"Since the day I met her over 20 years ago, she fought for me along with @rogerkumble to be Cecile." Blair added. "She took me under her wing and today is no different. I am so in love with my angel of a friend."
"May we all have a friend like this. I love you @sarahmgellar and my whole team of lovelies . I count my blessings. #friendsforever #kathrynandcecile."
Gellar responded with an equally heartfelt post.
"Our relationship began with me fighting for you," Gellar wrote. "And I will spend the rest of my life continuing to fight for you."
"This is one of those bumps in the road," Gellar added referring to Blair's recent MS diagnosis.
In October Blair shared an emotional Instagram post, revealing that she had recently been diagnosed with Multiple Sclerosis, a neurodegenerative autoimmune disease that affects the central nervous system.
"I have #multiplesclerosis . I am in an exacerbation," She shared in the October post. "By the grace of the lord, and will power and the understanding producers at Netflix , I have a job. A wonderful job. I am disabled. I fall sometimes. I drop things. My memory is foggy. And my left side is asking for directions from a broken gps. But we are doing it."
It's been a difficult journey for Blair since her diagnosis but as always her friends, especially Gellar, were by her side.
"Since my diagnosis at ten thirty pm on The night of August 16, I have had love and support from my friends , especially @jaime_king @sarahmgellar@realfreddieprinze @tarasubkoff."
And despite the challenges of her diagnosis Blair is facing her disease with inspiring courage.
In February Blair made her first post-diagnosis public appearance, dazzling onlookers at the Vanity Fair Oscars party as she walked the red carpet with the aid of a new custom created cane.
It was an emotional moment for Blair and her fans who applauded the actress for her bravery.
No doubt living with MS will present many challenges for Blair, but with the support of friends like Sarah Michelle Gellar it's going to be a much easier road to travel.
