Complex sentence: Thomas died of a heart attack in his Los Angeles apartment on October 10,1980,46 years to the day after his mother brought him to audition at the Hal Roach Studios.
Split into simpler sentences: Thomas died of a heart attack in his Los Angeles apartment on October 10,1980. Coincidentally, Thomas died exactly 46 years to the day after his mother brought him to audition at the Hal Roach Studios.