Def Jam and Phat Farm tycoon Russell Simmons has filed a petition requesting shared custody of his two daughters with model and designer Kimora Lee Simmons, ET Online reported this week.

Lee Simmons, who just turned 33, asked for sole legal and physical custody of the children when she filed for divorce from Simmons on March 25 -- requesting that her husband get "reasonable child visitation... accompanied at all times by the children's nanny and security personnel," according to USA Today. But Simmons filed his papers requesting joint custody on May 5.

The couple's daughters, eight-year-old Ming and five-year-old Aoki, have both modeled for the Baby Phat Kids Collection.

Simmons and Lee first met in November 1992 and married in the Caribbean in December 1998. Although they have been separated since March 2006, Lee Simmons didn't file her divorce papers until two years after the separation. Both have moved on: Simmons is now involved with model Porschla Coleman, while Lee Simmons has been dating actor Djimon Hounsou.

Russell Simmons, 50, co-founded the hip-hop label Def Jam in 1984; he also founded the clothing company Phat Farm, which he owned until selling it in 2004. In addition, Simmons created the HBO shows Def Comedy Jam and Def Poetry Jam.

Kimora Lee Simmons began her career as a fashion model and has been the head of design for Baby Phat since 1999. She stars in the reality-TV series Kimora: Life in the Fab Lane.

For expert advice on whether joint custody is right for your divorce, click here.