Reading in the bath is my idea of heaven! Any book is suitable, but for fun read Glenda Millard's Unplugged and giggle at Dee Huxley's wonderful illustration of the bath tub in the middle of a paddock.
It's also a good day to read or sing the poem Tiny Tim (Miss Lucy Had a Baby) or share it in picture book form. I like The Lady With the Alligator Purse by Nadine Bernard Westcott. There are just so many versions!