Connection of bathtub to shower

The mother! ...or nobody! ;)

Maybe, but don’t you think it will look too dark if there’s a wall in between?

Don't you have a ceiling light?

Even with artificial light, it still looks like a hole - if the children can really shower by themselves, you have to drill into them from the start to wipe off with the flap - purely a matter of discipline.

A wall would be too bulky and unnecessarily darken the space.

I like the idea of enlarging the shower and having a shelf for the bathtub.

I agree with @Lexmaul. It’s purely a matter of upbringing. Even smaller children can learn to use a squeegee.

Plastic as a shower wall also needs to be wiped off after showering, only it doesn’t stay as nice as glass over the years.

That is actually the bathroom cabinet :D

We will probably do it like this from the bottom of the plan:
120x90 shower with room-side glass element with inward folding door and bathtub-side fixed element.
20 cm shelf at the height of the bathtub
90x180 bathtub
Small shelf ~ 8 cm