Ryan welcomed his first child with wife Blake Lively over Christmas. And even though the 38-year-old had to embrace fatherhood a little earlier than expected (Blake's due date was given as early 2015), Ryan has revealed he is loving every minute of being dad.
Appearing on the Tonight Show on Monday (2 March), Ryan told host Jimmy Fallon that family life has been "so good" so far.
Gushing over his nine-week-old baby girl, Ryan added: "She's got me wrapped around her finger, I am a slave to the rhythm."
Although it seems the doting dad has been running on empty since his daughter's arrival, as Ryan revealed he and Gossip Girl star Blake are yet to get any sleep.
"Our baby in particular is - we think - allergic to sleep," he explained. "We think that she thinks she's protecting us from the sleep monsters... like 'oh, I've got to keep them up or the sleep monsters will get them'."
Ryan's comments come after Blake gave birth to their daughter late last year.
Following her birth, Blake and Ryan - known for being notoriously private - never confirmed the arrival of their newborn, until dad Ryan has been publicly talking about their baby in recent interviews.
Shortly after their daughter's arrival, it was reported the coupled had decided to name their baby Violet - however Ryan has since denied this.
He and Blake still haven't revealed which moniker they have chosen - although, the latest rumour - according to E! - is that the pair have picked James as their daughter's name.
While that may seem an unusual choice to some as it's usually chosen for a boy, the name 'James' has been used for girls before.
US actress Jaime King, for instance, was born with the names James before she shortened it.
And, don't forget, Blake herself is no stranger to having an androgynous name, so it wouldn't come as a surprise if her daughter has now followed suit!
Come on guys, spill the beans!
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