Anyone else struggle with bringing younger kids to older kid stuff

My kids are 8 and 15 and this has been an issue since having the second and only seems to get harder as the teens stuff gets longer and later. Everything seems set up for families of kids with like 2 year age differences.

It really doesn't help that my son has pretty severe ADHD, events for the teen happen long after his meds are worn off and they go way past his bedtime on a fucking school night. He gets extremely wound up and I have never been able enjoy anything because I'm too busy managing him.

The teen has a choir concert on Monday. At first I wasn't concerned because even though he argues and cries that he doesn't want to go he will enjoy himself and really get into it once he's there because he's very musically inclined. But these concerts have been like half an hour in the past and even that was a bit of a stretch. My daughter informed me that this year the concerts will be much longe because they will involve more choirs. Ugh.

I tried to see if she had any friends who could babysit but they're all either in choir or going to the concert to watch. I have to decide whether to bring him or choose a family member (me,.my husband or a grandparent) to stay home with him. If we take him we will probably have to leave as soon as daughter's choir performs and look like assholes because they want you stay for the whole thing.