roxy, my #1 drinking friso and she didnt have any poo problems. my #2 same like yours drinking BM in day and FM at nite. initially i gave him NAN HA (cos i tried friso bottle given by TMC but he kept votmitting and so TMC lactation specialist told me NAN HA resembles BM) then i switch to NAN Probiotics cos i find that NAN HA is abit oily. He has no problems with NAN and his poo is still yellowish soft kind..sometimes pasty type but not hard hard ones and he poos everyday.