Well all of this isn't pleasant and you were not late, on purpose.
BUT next time... I would have, ahead of time when you realized you were going to be later than usual... CALLED your parents and to tell them what was up. ie: the weather, cleaning the boat in the rain and the complications of that per timing.
But, yes, it was on Sunday, the next day is school. And perhaps, your parents are just thinking of your kids... going home so late at night and having their sleep interrupted, and school the next day. You mentioned that you/your Husband are usually late on Sundays, in picking up the kids.
And, meanwhile, your parents did NOT know... WHY you/your Husband were so late... in picking up your kids Sunday night. Because, no one called to tell them, what was going on.
So, that is another irritation for them.
In another vein: there have been times when my kids' Aunty has taken them out for a simple outing. I ALWAYS tell their Aunty that "school is tomorrow, they still have to finish homework and I don't want them to get back too late... they need their sleep. Tomorrow is Monday." So Aunty says fine. BUT... (and this has happened more than once), then Aunty... disregards my "instructions" to her.. and has kept my kids out LATE. And, it screws up the entire night time timing of things, for my kids, per bedtime and all of that. And yes, it IRKS me. To the point that, I now do not let Aunty take them out.... on Sundays, unless it is in the morning. Never in the afternoon again. She has in the past, had them out for like 5 hours. Straight. NOT good, in my book... because the next day is school for my kids. And there are things for us/them to do, before bed on Sunday nights.
Your parents and sister, were concerned about your daughter.
Being it was so late.
And there is school the next day.
I would not have been happy either, about it being 10:00pm, when the kids were picked up.
Maybe you guys can go out to the boat on Saturdays, instead????
Because late Sunday night, is not a good option it seems... for your parents or your daughter.