In Berkeley I also had to kneel to bathe Nate and it sucks. Mainly because I have bad knees anyway so this didn't really help the situation. Here I'm lucky that our bathtub has a wide enough side that I can sit on it comfortably.
But I did see these bath time kneeling mats that look amazing, I mean what a great idea. No regular bath or tub mat is thick enough to help, but these look really thick and plush, like a tumbling mat almost. These look like a great way to save your jeans, and your knees! Giggle has a couple of options, check them out -
This one is shaped like a whale, how cute!
Here is the top view of it -
That would make me happy I think, and you can hang it up from that loop if you don't want to keep it on the floor all the time. I share my bathroom with Nate (it's the only bathtub) so I would rather have things that make me smile.
This one folds up so it's more compact for storage or carrying between bathrooms I suppose as well -
Either way, you can't lose. Find them both here -