Casey Affleck and his wife, Summer Phoenix, are expanding their family.  The couple, both actors, are expecting their second child.

Summer is due sometime during the winter, according to their spokesperson Rebecca Feferman.

"They're very happy and excited about the new addition to their family," Feferman told The Associated Press.

Affleck broke the news to "ET Online" during an interview Saturday at the Toronto International Film Festival.

Affleck and Phoenix, tied the knot last year and have a 3-year-old son, Indiana August.

Both Casey and Summer are the siblings of some Hollywood headliners.  Casey is Ben Affleck's kid brother and Summer is the sister of Joaquin Phoenix and the late River Phoenix.

Affleck stars with Brad Pitt in the upcoming western "The Assassination of Jesse James by the Coward Robert Ford." His other screen credits include "Ocean's Eleven" and its sequels, and 1997's "Good Will Hunting."

Phoenix has appeared on the NBC series "ER" and in the 2002 HBO movie "The Laramie Project."