Back to the future (Robert Zemeckis, USA, 1985)
“Now, remember - according to my theory, you interfered with your parents first meeting. If they don’t meet, they won’t fall in love, they won’t get married and they won’t have kids. That’s why your older brother’s disappearing from that photograph. Your sister will follow, and unless you repair the damage, you’ll be next. ”
Got the trilogy on Blu Ray for Christmas - Great. Scott! It’s heavy!