"To all the amazing daddies out there that love their kids unconditionally like my mommy's daddy and my daddy, too...HAPPY FATHER'S DAY," the message read with a beautiful photo of her son holding a stick.
York's father, Erik Asla, posted the same photo with a message showing love to all four of his children, including the 1-year-old.
"As a father of four, Father's Day means I get four times the love. And little wooden sticks from this guy."
When Banks first made the announcement of their son's birth, she described York's features resembling his parents.
“The best present we worked and prayed so hard for is finally here,” Banks wrote in an Instagram post. “He’s got my fingers and big eyes and his daddy Erik’s mouth and chin.”
Banks and Asla welcomed their son in January 2016 through a gestational surrogate. The couple reportedly met on the set of Norway's Next Top Model.