The duo have been friends for two decades, since meeting on the set of "Cruel Intentions."
On Thursday morning, Blair -- who recently opened up about her multiple sclerosis diagnosis -- posted a selfie she took with her "angel of a friend" to thank her for tucking her in, bringing her dinner and loving her unconditionally.
"This girl (always my girl) is everything," Blair captioned the sweet shot. "She tucked me in and brought me dinner and loved me up. I woke with so much love for Sarah Michelle Gellar. Since the day I met her over 20 years ago, she fought for me along with ['Cruel Intentions' director] Roger Kumble to be Cecile." Blair played Cecile Caldwell in the 1999 drama/thriller.
"She took me under her wing, and today is no different," the actress continued. "I am so in love with my angel of a friend. The best." Blair went on to say Gellar and her "team of lovies," including Jaime King, shared her bed with her and have been there for her "very step of the way."
"May we all have a friend like this," she concluded. "I love you, Sarah Michelle Gellar, and my whole team of lovelies. I count my blessings. #friendsforever."
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This girl. (Always my girl) is everything. 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. She took me under her wing and today is no different. I am so in love with my angel of a friend. The best. @janeylopatey also shared the love on my bed yesterday. She and @karenzambos @jaime_king and this one even threw me my baby shower and are there every step of the way. May we all have a friend like this. I love you @sarahmgellar and my whole team of lovelies . I count my blessings. #friendsforever
Gellar reposted her friend's photo and caption, adding, "Our relationship began with me fighting for you, and I will spend the rest of my life continuing to fight for you. This is one of those bumps in the road that I truly believe within the year we will barely remember. (And thanks for leaving the part out where I proceeded to fall asleep in your bed -- lots of help I am lol)."
Blair made her first public appearance since announcing her diagnosis at Sunday's Vanity Fair Oscars Party. She sported a gorgeous gown, matching cape and a cane personalized with her monogram. The support on social media was overwhelming, and SMG led the way.
"This is my dear friend, Selma Blair," she captioned a photo of the actress on the red carpet. "Last night, she stood on the world stage for the first time since being diagnosed with MS. And later this week, she is taking an even bigger step and speaking publicly on 'Good Morning America' (with my girl crush, Robin Roberts). To say I'm proud would be a gross understatement."
"When I have a cold, I want to hide from the world under my covers, but not Selma," Gellar continued. "She is facing this diagnosis the way she faces everything -- with dignity, grace and head on. I know the support and encouragement that she has received on this platform has truly been a source of strength for her. This is not an easy journey, but Selma will not let this define her. I love you, James."
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This is my dear friend @selmablair Last night she stood on the world stage for the first time, since being diagnosed with MS. And later this week, she is taking an even bigger step, and speaking publicly on @goodmorningamerica (with, my girl crush @robinrobertsgma ) To say I’m proud, would be a gross understatement. When I have a cold, I want to hide from the world under my covers. But not Selma. She is facing this diagnosis, the way she faces everything, with dignity, grace and head on. I know the support and encouragement that she has received on this platform has truly been a source of strength for her. This is not an easy journey, but Selma will not let this define her. I love you James.
The ABC News interview Sarah referred to in her sweet post aired Tuesday morning -- and it took the world by storm.
Blair spoke slowly yet positively about her debilitating disease. Her voice quivered and jolted, but she smiled anyway.
"I am doing very well," the actress told Robin Roberts. "I am very happy to see you, being able to just put out what being in the middle of an aggressive form of multiple sclerosis is like. So my speech is -- as you'll notice -- I have spasmodic dysphonia right now."
MS is an unpredictable, often disabling disease of the central nervous system that disrupts the flow of information from the brain to the body, causing problems with vision, balance and muscle control. Spasmodic dysphonia -- a symptom of the chronic disease -- is caused by involuntary movements of one or more muscles of the voice box, otherwise known as the larynx.
"It is interesting to put it out there, to be here, to say, 'This is what my particular case looks like right now,'" she added.
Blair was diagnosed in August of last year, and when she first opened up about her diagnosis in October, she described it as a relief because it gave some clarity to years of symptoms. She speculated that she's likely had MS for 15 years. It was friend and "Saved by the Bell" alum Elizabeth Berkley who recommended Blair see her brother, who was able to provide the diagnosis after seeing lesions on her MRI.
Upon receiving the news, Blair said she cried. "They weren't tears of panic; they were tears of knowing I now had to give in to a body that had loss of control," she explained. "And there was some relief in that because ever since my son was born, I was in an MS flareup and didn't know. And I was giving everything to seem normal. And I was self-medicating when he wasn't with me. I was drinking, I was in pain. I wasn't always drinking, but there were times when I couldn't take it, and I was really struggling with, 'How am I gonna get by in life?'"
To see her full interview, click here.
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