From your description, I believe that it is probably past time the two children should have been taking separate baths. There are tremendous amounts of peer pressure at school and on the playground for boys to have sexual relationships with girls, and I suspect your grandson has started to succumb to those pressures.
Talk to your daughter-in-law and tell her that she should consider stopping the practice herself and that you will no longer allow this practice to occur when you are baby-sitting the children - either in your house or theirs.
Kids know when it's time ..my girlfriend let's her son age 8 an daughter age 12 shower together .
i think they r to old to be bathing together also.
aussiemum sorry to hear about ur childhood!!!!!!!
I would be suspicious and monitor their behaviour together more closely. It may be nothing, but I truly believe in women's intuitiion. And you were very observant to notice those details about the buttons.
My brothers had a room downstairs under the house where there sexually abused me from about the age of 9 or 10 till I was 12 on a regular basis.
Meanwhile my dad was upstairs and never checked on us. Mores the pity...
Good luck.
They are old enough to be mutually curious. It should probably have ended some time ago.
I would say that kids of different genders at these ages should no longer be bathing together, especially if there is some possible impropriety going on. Other than time and water savings, I would question what benefit they are getting from it that couldn't be achieved in some other way.