Strolling around Sydney's Royal Botanic Gardens in Australia, Britney Spears appeared happier than she has in years. And no wonder: She had her sons, Sean Preston, 4, and Jayden James, 3, and her agent turned boyfriend, Jason Trawick, by her side.

But for Britney, 27, one thing would truly make her family complete: another baby -- with Jason. "Britney and Jason have been talking a lot lately about having kids," reveals a Spears family insider. "She's madly in love with her boys, but she'd love to have a little girl."

Jason, 37, is on the same page. "He can't wait to have kids," the insider says. "He's amazing with Britney's sons, and he's not a partyer or a player. He loves Britney and wants to start a life with her, so she doesn't have any fears about him as a daddy."

For more on Britney and Jason, pick up the new issue of Life & Style, on newsstands now!

Photo Credit: Retna