I would really like to be able to let parents/teen siblings help the toddler SHOWER. Tiny living is almost impossible with a toddler, even if you have enough room for them as a child/teen. Not to mention in a normal non-tiny living home that is short on space but too poor to move out, this would be a godsend.
I generally try not to have tubs because of the time it takes sims to bathe, that and baths pretty much let you sit in your own filth and that just grosses me out. So yeah, toddlers being able to be showered, or "clean up toddler" giving MORE hygiene would be great. I mean, my parents let me play in the shower as a toddler. It was their way of keeping me from zipping out to play in the rain. I was a fast toddler, apparently. Used to run down the street before my mom could blink.