My 10-month-old DS breastfeeds while we are together. While at daycare he drinks breast milk I pump at work from bottles. He eats three meals a day and drinks water from sippy cup. My question is that he only drinks 4oz maybe 5oz at a time, he never has wanted to drink 8oz. Other babies drink 8oz at this age. Is this typical of breatfeed/breastmilk feed babies?