My 8 month old has always been breastfed but recently i returned to work and am still expressing. I can't express enough so I supplement with formula. However it seems to be causing him terrible nappy rash. I read formula can cause this and it seems to make sense as its only since he started childcare (where I give them bottles of formula) and it clears up on the days he's home with me and breastfeeding. I know it's not the childcare workers as they change him frequently and put lots of cream on and together we've tried other things. It seems as soon as the poo after formula touches his bum it burns instantly. I currently use Bellamy organic infant formula. Does anyone know a formula that doesn't cause nappy rash I could try?