Chris Kelly of the Duo Kris Kross Dies at 34 Jeff Kravitz/FilmMagic, Inc., via Getty Images Chris Kelly, a k a Mac Daddy, right, with Chris Smith, a k a Daddy Mac, performing as the duo Kris Kross in 1993. A pair of moppets with braided hair who wore their clothes backward, the kid duo Kris Kross was one of the unlikely music success stories of the early 1990s, multiplatinum stars who bridged hip-hop to pop, had indelible style, and showed that rap could sustain a youth invasion. In the duo, Chris Kelly was the Mac Daddy to Chris Smith's Daddy Mac. They had met in the first grade and were discovered in the early 1990s at the Greenbriar Mall in Atlanta by Jermaine Dupri, who molded them into the first commercially successful teen-oriented hip-hop act. Mr. Kelly died on Wednesday after being found unresponsive in his home in Atlanta. According to a police report, Mr. Kelly's mother, Donna Kelly Pratte, said he had been using cocaine and heroin before his death. The Fulton County Medical Examiner's office said toxicology reports would not be available for several weeks. James Christopher Kelly was born on Aug. 11, 1978, grew up in Atlanta, and was barely in his teens when he became a star. Kris Kross's debut album, "Totally Krossed Out," released on Ruffhouse/Columbia in 1992, was one of hip-hop's first and loudest pop crossover statements, topping the Billboard album chart and going platinum four times over. "Jump," the duo's debut single, was the No. 1 song in the country for eight weeks, at the time the longest run for a hip-hop song. Kris Kross was "the first major hip-hop artist to come out of Atlanta," said the group's former manager, Michael Mauldin. There was also no real precedent for the success of rappers of such a young age. "We didn't have nothing to measure against at that time," Mr. Mauldin said, "but we did in older times: Jackson 5, New Kids on the Block." At its peak, Kris Kross toured with Michael Jackson and recorded a song for the popular Nickelodeon cartoon series "Rugrats." But as the group aged into more mature subject matter, its popularity waned. Two subsequent albums were successful, but less so: "Da Bomb" (1993) went platinum and the tougher, West Coast-influenced "Young, Rich & Dangerous" (1996) went gold. The pair reunited in February for the 20th-anniversary concert of So So Def, the influential label founded by Mr. Dupri in the wake of Kris Kross's success, and were slated to be part of a coming tour celebrating the label. In the meantime, Mr. Kelly studied audio engineering, ran a small record label and owned a day-care business with his mother. In addition to his mother, survivors include his stepfather, Jim Pratte, and his grandmother Rosina Williams. During the lean years, Mr. Kelly could get frustrated, said DJ Nabs, the group's D.J. and a longtime friend of Mr. Kelly's: "People looked like they turned their back on him." But even though the style the group pioneered had changed, Mr. Kelly never fully left his glory years behind. In an interview with Yahoo earlier this year, he proudly proclaimed, "I've worn my pants backward since 1991, never frontward."