I'm pretty sure 90% of park attendees would be glad to let you leave the line. It has nothing to do with having 2 parents. I understand some people have very strong feelings about wanting everyone to stsnd in line the whole time, never, ever, ever leaving. Those people are in the severe minority, and they've probably all posted on this thread. I have never blinked an eyelash at a parent and child, or even a teenager or adult saying they needed to get back to their family from the restroom. I've never seen anyone else upset either. We all know the lines are long. We all know you're supposed to stay hydrated, especially in the summer. So if you're in a 2 hour long line what do you want people to do? I certainly don't want to be the person who gets seated in the ride vehicle after the kid who peed her pants because she didn't want to make her siblings go to the end of the line. I also don't want to be in line with someone who is about to pass out or start vomiting from heat exhaustion because they didn't leave the line and get water. People need to just relax, use a little empathy and understand that sometimes you can't stand in line for hours at a time and not leave. Off these boards, the general public is mostly happy to accommodate you and make the wait doable. If you have an ADR timed such that one family, or even 20 families having a change in line would cause you to miss it, perhaps you need to plan your time differently. Most rides at wdw load a whole lot of people rather quickly. You would need dozens, if not hundreds of people to somehow get ahead of you to push a 5 minute wait to 30 minutes.