We have had celebrity baby bonanza, hence the weekend post. Four celeb babies…they should start going on play dates together as soon as they're able!

Heartiest congratulations to Nicole and Joel, Christina and Jordan, Courtney Thorne Smith, and David Alan Grier.

Little Miss Richie Madden, the inspiration for the Richie-Madden Foundation, came into the world Friday, according to Usmagazine.com. Nicole and Joel had a baby girl, Harlow Winter Kate Madden. Very pretty name, that is, inspired by the 1930s blonde bombshell, Jean Harlow.

The rep for Richie-Madden told the magazine that Harlow Winter Kate was born Friday at Cedars-Sinai Medical Center in L.A. She weighed 6 lbs., 7 oz.

Since becoming pregnant, a more socially-aware Nicole and Madden have launched the Richie-Madden Foundation to assist kids in need.

Also popped:

Christina shared the maternity ward with Nicole. On Friday, she,too,was relieved of her massive belly bump. Star magazine says her little boy arrived at 4 p.m. and mom, dad and baby are doing well.

Also joining the mommy brigade for the first time Friday was Courtney Thorne Smith, 40.

She had a baby boy as well, named Jacob Emerson Fishman.

On Thursday, funnyman David Allan Grier and wife Christine Kim welcomed their baby girl, Luisa Danbi Grier-Kim.