If you have been following me on Pinterest it would come as no surprise that we tried this idea. We made enough for Caspar to give to some of his friends. You can see we put glitter into the yellow as Caspar wanted to add some sparkle for one sparkle loving friend. Thank you to Meryl for what I think is a fantastic and original idea. You can see the instructions on My Bit of Earth here. 

Caspar tested all three colours. None of them stained or coloured his hands or the bath. The bath water ended up slightly brown as he used all colours at once. Caspar also enjoyed writing on Otis's back. So much fun.