Jessica Alba is a mom again: The actress has welcomed her third child -- and first baby boy -- with husband Cash Warren.

Alba had an eventful New Year's Eve, giving birth to Hayes Alba Warren on December 31. According to the actress, who announced the exciting news herself in an Instagram post, her newest little bundle was the "Best gift to ring in the New Year," and she and Warren "feel so blessed."

Hayes joins big sisters Honor Marie, 9, and Haven Garner, 6 -- and his siblings are "already obsessed with their new baby bro," Alba said.

In an Instagram post of his own, Warren revealed that Hayes wasn't actually expected to arrive for a few more days, but said that the family "couldn't be any happier" with the way things worked out.

"Your Mamma is the strongest woman I know ... you're so lucky to have her by your side," Warren wrote, addressing his new son. "You have two amazing sisters who already adore you and I know you'll be thankful to have them guide the way."

Alba, 36, and Warren, 38, have been married for nine years. Congrats to the new family of five!

[via: Jessica Alba/Instagram, h/t People]