The Definitely Maybe actor has only just joined Instagram, but it didn't take him long to give us all a glimpse at his baby girl. And when we say glimpse, we mean it!
In his photo, Ryan made sure to keep James' face well out of view, instead choosing to photograph her teeny tiny hand clutching his.
How sweet is that?!
Alongside his photo, the star joked: "Thumb wrestling isn't always fair. Curiously, my hand is the small one."
Despite Ryan's photo only showing a fraction of his baby girl, fans were still excited to get a first look at James and many were quick to comment on his post, with over 47,000 users liking it.
One follower said: "So beautiful." While another told Ryan: "Parenthood is the best. Congratulations!!"
Ryan and his wife Blake Lively welcomed their daughter James late last year, announcing her arrival a few weeks after her birth.
Since then, both Ryan and Blake have been gushing about their new arrival, with the Gossip Girl star revealing the pair have even been competing to steal James' first word.
Appearing on The Tonight Show with Jimmy Fallon, she said: "We're total rivals... I hear [Ryan] like 'dada, dada' then I walk in the room and he'll be like 'mama'. How dare he do that! The word dada is banned in our household!"
"[James] has to say mama first. I do everything, [Ryan] does nothing," she joked.
Ryan, meanwhile, has said James already has him wrapped around her little finger! Aww!
Not only does the tot, have two superstar parents, but Blake revealed James has three very cool godmothers too. The blonde beauty bestowed the honour on her very close pals and Sisterhood of the Travelling Pants co-stars America Ferrera, Alexis Bledel and Amber Tamblyn.
Amazing, right? We're not jealous at all...
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