If you don't want to confront her, or don't think it'll go well, I would just tell hubby they are getting home too late on Sundays and need to come straight home after swimming. They can visit with aunty before.

Washing their hair is just weird :lo:
I believe in manicures. I believe in overdressing. I believe in primping at leisure and wearing lipstick. I believe in pink. I believe that laughing is the best calorie burner. I believe in kissing, kissing a lot. I believe in being strong when everything seems to be going wrong. I believe that happy girls are the prettiest girls. I believe that tomorrow is another day and I believe in miracles.
Audrey Hepburn