I've always bathed both Ty and Hanna together but it's been really fun recently with Hanna being able to interact more.
Ty is such a great big brother...caring, sharing, protective..etc etc. so, bath time is no exception. He makes sure she has toys and plays in her little tub with her...haha.
I have to take documentation of their sweet, loving sibling behavior now incase there is a time when they don't get along as well...but surely the teen years won't allow happen..haha!