Schatzie has done this quite a few times actually. She likes to cat walk along our garden tub but theres those few instances when she slips and falls in with me.
And I know exactly how hard it is to bath one handed, lol.
There are even those times when I hear "something going on" so I walk in and Schatzie's in the tub (no water) w/ her toy (s). The bath tub is a hug toy to her, she's sooo silly.