LUCIANA BARROSO and MATT DAMON

Little Gia Zavala Damon has two big sisters waiting for her at home - two-year-old Isabella and Alexa, Barroso's 10-year-old daughter from a previous marriage.

Damon's spokeswoman reports the new arrival is "a healthy, beautiful baby girl."

Ironically, little Gia was born on the same day that Jennifer Garner, the wife of Damon's best friend Ben Affleck, confirmed she's pregnant with the couple's second child.

Damon recently joked about his female-dominated household, stating, "I'm so outnumbered down here, it's crazy."

Source: WENN