Zach Galifianakis hasn't let fame go to his head. In fact, the 43-year-old actor invited his formerly homless friend, 87-year-old Elizabeth "Mimi" Haist, to be his date at The Hangover III premiere in L.A. May 20.

The pair became friends in 1994 when Galifianakis was trying to launch his comedy career in L.A. During that time, he visited nearby Fox Laundry, where Haist volunteered and survived off tips from customers. The two stayed in touch over the years, and two years ago, Galifianakis bought Haist a one-bedroom apartment. He now pays her rent and utilities.

PHOTOS: Summer movie guide

Before Monday's Hangover III premiere, Haist told The New York Daily News she was "looking forward" to catching up with her old friend. "I like the excitement of it," she explained. "If he's in town, he takes me. Otherwise he lets me take a friend. I dress up nice and a friend helps me with my makeup. It's fun, not something I've ever dreamed I'd experience. The limo takes me home afterwards."

VIDEO: Ed Helms gets a face tattoo in The Hangover 2

Galifianakis always extends an invite to the star-studded afterparty. "I drink lemon drop martinis with Grey Goose vodka," Haist said.

PHOTOS: Do these Hollywood hunks look better with facial hair?

The North Carolina native, who wed Quinn Lundberg in August 2012, spoke to Us Weekly about the final film in the Hangover trilogy at Monday's premiere. "I'm not sad. I'm really excited about being able to celebrate this with the fans across the country," said Galifianakis, who plays Alan Garner. "This is the last one, so we kind of wrap things up nicely with the third one."

This article originally appeared on Zach Galifianakis Takes Once Homeless Friend to Hangover III Premiere