Kevin Jonas
is a natural! 

The oldest Jonas Brother -- who welcomed his first child with wife Danielle over the weekend -- shared the sweetest snap of him holding his baby girl in the delivery room.

"My beautiful girl so proud to be a dad. Alena Rose has stolen my heart. @dreft #ad," he tweeted with the cute picture. 

Both of Kevin's brothers have shared their excitement about their new niece, who arrived the same weekend as their grandfather's memorial service. 

"My grandfathers memorial was yesterday. Today we welcome a new addition to the jonas family. God is great. Can't wait to meet my new niece," Nick Jonas tweeted on Sunday. 

Joe Jonas shared his sentiments writing, "As one life ends, another begins. Incredibly happy to be an uncle for the first time. Welcome to this world my beautiful niece."

She's a real cutie! Check out even more personal pics of celebrity kids in the gallery above.