Simon Helberg with wife Jocelyn Towne and baby girl Adeline in Los Angeles, CA on June 21, 2012. Credit: Splash News Online

Whoa baby!

Big Bang Theory star Simon Helberg stepped out in L.A. Thursday, showing off his latest, greatest project to date: his first child with his love of nearly a decade, Jocelyn Towne.

Helberg's wife gave birth to the couple's daughter, Adeline, May 8.

"The family is thrilled," a source told Us Weekly of the proud new parents at the time, adding that Helberg, 31, channeled his Big Bang Theory character prior to welcoming Adeline -- by doing lots of research.

"Simon is excited to be a father," the source shared. "He's been doing his reading!"

The Let Go actor met Towne in Los Angeles; they dated for several years before making it official in a 2007 ceremony. Currently, they reside in Charlie Sheen's former Hollywood estate, which they purchased from the actor for $3 million last November.