Aaron Carter: Party Animal

12/18/2006 2:46 PM PST
Former Backstreet Boy Nick Carter's lil' brother Aaron got his Lohan on and partied like an underage rock star at his 19th birthday bash on Friday.

Aaron, along with twin sis Angel, took over L.A. hotspot Shag and celebrated Carter-style ... by getting into a cake fight and chugging large quantities of a clear unknown liquid. 'Dem Carters is classy.

The "House of Carters" celebrity wattage was only eclipsed by Hulk Hogan's son Nick and porn star Mary Carey getting their groove on.