If all goes according to plan, the Brady boys will be learning a thing or two from their younger sister, Vivian Lake.

Speaking to ESPN Dec. 9, New England Patriots quarterback Tom Brady**, 35, opened up about his newest family member; his wife, Gisele Bundchen**, gave birth in Boston Dec. 5. (The newborn joins big brother Benjamin, 3, and half-brother John, 5, from the football player's previous relationship with actress Bridget Moynahan**.)

"I'm in trouble!" Brady laughed. "I grew up in a house with three sisters. I think it's great for my boys to have a girl in the house, just to understand at least a little bit about what makes a woman tick -- not that I can certainly figure that out, because I can't. She's a beautiful little girl."

Fatherhood, Brady explained, is his most important responsibility. "I love playing football. I love coming to work every day," the athlete said. "But also, being at home, and giving those boys my attention, and my affection, and my discipline, and being a good parent is so important, because I grew up with two of the best parents a son could ever ask for."

Bundchen, 32, announced her daughter's birth via Facebook Dec. 7. "We feel so lucky to have been able to experience the miracle of birth once again and are forever grateful for the opportunity to be the parents of another little angel," the Brazilian supermodel wrote. "Thank you all for your support and well wishes. We wish you and your families many blessings."

This article originally appeared on Usmagazine.com: Tom Brady Jokes About Raising Daughter Vivian Lake: "I'm in Trouble!"