The actor is already father to daughter Iona, 15, and son Joseph, 17, from his previous marriage
Now there’s a Mother’s Day to remember!
“On this beautiful Mother’s Day evening…” McKidd, 44, captioned a black-and-white photo of Goldrath cuddling with their newborn.
“Welcome little Aiden to our family and to the world!” he continued. “Arielle, you’re the most amazing mother and I love you both so much! #happymothersday #forever #weeAiden #Arielle #newlife.”
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McKidd made the surprise announcement in March that he and Goldrath, a private chef, were married and expecting a child together.
“Arielle and I are so happy to announce our marriage and new baby, who is soon to join our growing family,” he revealed in a post on his website.
“My kids are happy for us too and are looking forward to the arrival of their newest sibling!” continued the actor, who shares daughter Iona, 15, and son Joseph, 17, with ex-wife Jane Parker. (The two, who wed in 1999, separated in October 2015.)
“There’s much to be grateful for and we’re thrilled for the adventures 2018 will bring us all!” he concluded.
McKidd, who plays former U.S. Army trauma surgeon Owen Hunt, joined Grey’s Anatomy during its fifth season as a love interest for Sandra Oh’s Christina Yang. Though their characters married, they divorced before Oh left the show. Hunt is now married to Amelia Shepherd, portrayed by Caterina Scorsone.