Rumer Willis and Pete Wentz?

Rumer Willis, the oldest daughter of Demi Moore and Bruce Willis, has entered into a comparatively age-appropriate hook-up with Pete Wentz, reports The Sun. The two were spotted holding each other's hands -- and then some -- at Hollywood hotspot Shag this weekend.

Rumer is 18 years old, and Pete, at 27, is only a year younger than Rumer's mom's husband, Ashton Kutcher. Her father has been linked in recent years to Brooke Burns, who is -- you guessed it -- barely a year old than Pete.

Wentz, the lead singer of Fall Out Boy, has dated both Ashlee Simpson and Lindsay Lohan in the past year. Interestingly, Lindsay and Rumer were often spotted hanging out together late last year, much to the reported chagrin of her step-dad, Ashton, who probably borrowed Lindsay from his buddy Wilmer Valderrama more than once back in the day ... oh what a tangled web we weave.