It's your kids, Marty. Something has got to be done about your kids.
3 seconds sound clip from the Back to the Future Part II movie soundboard.
You can hear this line at 00:02:08.095 in the Blu-ray version of the movie.
Quote context
[...]
- Jennifer's here. We're gonna take the new truck for a spin.
- Well, bring her along. This concerns her, too.
- Wait a minute, Doc. What are you talking about?
- What happens to us in the future? What, do we become assholes or something?
- Oh, no, no, no. You and Jennifer both turn out fine.
- It's your kids, Marty. Something has got to be done about your kids.
- Hey, Doc, we better back up. We don't have enough road to get up to 88.
- Roads? Where we're going, we don't need roads.
(DeLorean flying and going into time travel)
[...]