Blake Lively and Ryan Reynolds shared the very first photo of baby James on Thursday, May 14. Credit: courtesy of Ryan Reynolds/Instagram

Tiny hands! Blake Lively and Ryan Reynolds shared the very first photo of their baby girl James via Instagram on Thursday, May 14, debuting a shot of her tiny little fingers wrapped around Reynolds' thumb.

The shot, first shared by Reynolds, 38, included the caption: "Thumb wrestling isn't always fair. Curiously, my hand is the small one."

Lively, 27, quickly regrammed her husband's social media update and added under her account: "...and with that, my husband @vancityreynolds joins Insta."

After welcoming her first child with Reynolds in December, Lively quickly rebounded to promote her latest movie, romantic period drama The Age of Adaline. During her press tour, the bubbly Gossip Girl alum spoke in detail about first-time parenting with her hunky husband and the realities of raising a newborn baby.

"You never know when you're gonna get crapped on or when you're gonna get a big smile or when that smile immediately turns into hysterics," Lively told the Los Angeles Times last month about her 4-month-old tot. "It might be like living with a drug addict. But you have a baby and you think, 'I can't imagine ever not having a baby,' because they grow up so quickly. I'd be an 80-year-old woman with a baby if I could."

While the stars have yet to reveal their daughter's face (they chose to keep her name hush-hush until March), Lively told Kelly Ripa and Michael Strahan last month that baby James looks a lot like her dad. "I think she looks like her daddy," Lively noted. "I want a maternity test! ... If not, I'm not sure about this kid... She never left our sight, but..."

She also gave some insight on why they named their daughter James. "It's a family name," the star said in the same interview. "And I liked having a boy's name, so I thought I'd pass it on."