August 31, 2005 -- IT'S good being Dr. Phil's son.

Jay McGraw, 26, son of the tough-love TV psychologist, is engaged to marry former Playboy playmate Erica Dahm, one of the triplet Dahm sisters, a spokesman for Dr. Phil confirmed yesterday.

The triplets were featured on young McGraw's "Renovate My Family" series on Fox. On the show, the sisters were usually part of a wrecking crew that brought down the home each week of a family that wanted a new house.

The couple will wed in Los Angeles, but the date was not disclosed.

Dahm, 27, and her two sisters appeared in the December 1998 Playboy.

Jay is a best-selling author of self-help books for teens and young people. Post wire service