09/01/2009 at 02:20 AM EDT
and Joel Madden
are the proud parents of a baby boy, PEOPLE confirms.
"In the middle of night, the very early hours of September 9, 2009, Sparrow James Midnight Madden was born to Nicole Richie and Joel Madden. He weighs 7 lbs. 14 oz. Nicole, Joel, Harlow and Sparrow are all doing
well. Thank you for all of your good wishes," the couple wrote on Richie's Web site
The newborn joins older sister Harlow Winter Kate Madden, born in January 2008
"We're very, very blessed," Madden, 30, told PEOPLE
on Aug. 6 of the approaching event. "We've already had one healthy kid, and that's all you can ask for as a parent – healthy kids."
Richie, 27, who's enjoyed a new low-key lifestyle
at home since the birth of Harlow, still keeps active with various business projects, including a maternity line
for A Pea in the Pod and her House of Harlow 1960
The couple also run the Richie Madden Children's Foundation
, which they launched in 2007 to provide grants to health-care and education nonprofits.
"I don't think you can plan anything about having a child," Richie told PEOPLE
back in October 2008. "It's something completely new, so you just have to go with whatever works for you. There's a million different ways to be a mom."
Leave your congratulations for Nicole and Joel at PEOPLE's Celebrity Baby Blog