Yes, there are many urban legends about crazy curses that affected many of the cast members of all three Poltergeist movies. Not to take away from this post dedicated to Heather, I encourage you to read more about that over at TheBeyond.
Full Name: Heather Michele O'Rourke
Born: December 27th, 1975 in San Diego, California
Best Known For: Carol Anne in Steven Spielberg's Poltergeist, Poltergeist II and Poltergeist III.
Other Notable TV & Movie Appearances: Our House, 12 episodes of Happy Days, several episodes of Webster, CHiPs, Fantasy Island
Heather's first appearance on Happy Days.
An original news broadcast from 1988 announcing Heather's death.