Selma Blair Is 'So Proud' as She Celebrates Son Arthur's 12th Birthday: 'Forever My Favorite'

Selma Blair shares son Arthur Saint with ex Jason Bleick

Selma Blair is celebrating a big day for her not-so-little boy.

On Tuesday, the Legally Blonde actress, 50, posted a tribute full of photos old and new on Instagram in celebration of son Arthur Saint's 12th birthday.

Alongside a collection of photos of the tween, whom she shares with ex Jason Bleick, she wrote, "My Saint, Arthur, happy birthday 🎂."

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"This has been the most incredible life with you. Forever my favorite, I know you are going to have the best year yet," she continued.

"I am so proud of who you are and have become. Usually 🦁. The most adorable little kid has grown into a 12 year old!!!! 🐣🦅. I love you and I like you. Massively. 💛 mom."

Blair opened up about her son's involvement amid her battle with multiple sclerosis in her documentary Introducing, Selma Blair, which premiered last October. A scene from the documentary shows Arthur shaving his mom's head prior to her life-altering stem cell transplant in 2019.

"It was to have him be a part of it, help him be in control of maybe like a first image of Mom looking different," Blair told Entertainment Tonight of letting Arthur perform the haircut. "That was pretty easy and a nice moment, and it makes me feel better knowing Arthur has a say — not a say, really, but is included."

Blair also noted that Arthur has already forgotten some of the moments featured in the documentary. "There is so much I realize he was really young he didn't remember," she added at the time.

During the actress' time on Dancing with the Stars last year, her son made an appearance and applauded his mom's efforts.

"I'm really proud of her," he told Access Hollywood. "It's just wonderful that she does this stuff and moves around."

"It was amazing," he added. "Even the judges were moved by it."

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