Selma Blair commemorated her little boy's sixth birthday with a heartfelt message and a sweet snapshot.
The actress took to Instagram on Wednesday to celebrate son Arthur Saint's special day with a heartwarming black-and-white photo of the birthday boy about to make a wish and blow out the candle on his cupcake.
"Happy sixth!! Birthday! #arthursaint you have my heart. You are my light," the 45-year-old American Crime Story star captioned the cute pic.
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Blair shares Arthur with her ex-fiancé, Jason Bleick. The former couple, who began dating in 2010, welcomed their son in 2011. They later ended their engagement in September 2012.
Blair -- who is getting ready to head back to TV with the upcoming series reboot of the 1980s cult classic Heathers-- has frequently taken to Instagram to share some of her sweet mother-son moments, and the pair couldn't be more adorable together.
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