05/26/2008 at 01:00 AM EDT
After four months of nesting at home with baby girl Harlow, Nicole Richie
is "slowly but surely" getting back to work, she tells PEOPLE. "After having the baby, obviously I had to focus all of my attention on her. I had to get back in a place where I was mentally able to give myself to other people." Her first order of business: work with the Richie-Madden Children's Foundation, the nonprofit she launched in December with her boyfriend, Good Charlotte singer Joel Madden, 29. On May 8 the couple spent a day with L.A.'s Beyond Shelter, which fights homelessness and poverty among families with children. Touring a housing complex, "we met a woman who has seven kids and saw the mattresses stacked in the living room," says Richie, 26. "It really gives you [perspective]." The foundation is also gearing up for a national project to benefit moms in need, launching this fall—about the same time as Richie's jewelry line for Mouawad. The former Simple Life
star is also in talks to turn her novel The Truth About Diamonds
into a TV show and plans to produce and act. Although the couple haven't decided if the whole family will hit the road for Good Charlotte's summer tour, they are certain Harlow will join them in giving back. Says Richie: "As soon as she's old enough, she will be out here with us."