Playboy magazine founder Hugh Hefner and his wife, Kimberley Conrad, have arranged for a playmate for their 10-month-old son.

The couple disclosed that they are expecting their second child in September. Their first child, Marston Glenn Hefner, was born on April 9, Hefner's 64th birthday."They are thrilled. He said it was a playmate for his son," said Hefner spokesman Bill Farley.

Hefner and the 27-year-old Miss Conrad, Playmate of the Month in January 1988 and Playmate of the Year in 1989, were married at the Playboy Mansion in Holmby Hills on July 1, 1989.