Cobie welcomed baby Shaelyn Cado Killam on May 16, People reported.
This is the first child for Cobie and her fiance, actor Taran Killam.
The "How I Met Your Mother" starlet shares the screen with fellow new mommy Alyson Hannigan, who welcomed daughter Satyana in March.
While the two castmates were pregnant, they bonded over their growing bellies and often shared stories on set.
"You really can't help it, because you have babies on the brain, and you can't help but talk about it a lot…. From creams, doctors, birth methods, dilation … You talk about everything," Cobie previously told People.
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