Ds started on solids about 2 weeks ago and is straining to poo and crying quite a bit. He has only had fruit and veg (no banana) so far. I haven't been giving him water as he is underweight so I bf before and after solids. Is water better for constipation than bm? I thought bm would be ok as 'breastfed babies don't get constipated' but does that only apply pre solid food?