"As 2012 winds down and Thanksgiving approaches, I have much for which to be thankful -- personal, professional, and Presidential. However, nothing can match the joy and excitement my husband and I felt when we recently welcomed our second baby boy," Banks wrote in her online message.
"Magnus joins older brother Felix, thus commencing a decade or more of close hand to hand combat. Like Felix, Magnus was born via gestational surrogate. This experience has exceeded all expectations, taught us a great deal about generosity and gratitude, and established a relationship that will last a lifetime," said Banks.
"I am also so very thankful to our family and friends for their support throughout this process, as well as the Center for Surrogate Parenting for helping make all this possible. I now turn my attention to managing two boys under two. For which I am thankful. And all their poop. For which I am less thankful. Wish me luck."
Banks married author and producer Max Handelman in 2003. Their son Felix is 20 months old.
The actress has appeared in the films "Seabiscuit," "The 40-Year-Old Virgin," "Zack and Miri Make a Porno," "W.," "Role Models," "Wet Hot American Summer," "The Hunger Games," "People Like Us" and "Pitch Perfect." She also plays a recurring role on TV's "30 Rock."