my DD done this and still does sorry to say lol. she is gettin alot better but we were fighting to get 100 mls each bottle for awhile there.
now we r up to a 240 bottle but she usually leaves 60 to 80 mls each time. i was really worried at the start but the doc and nurses told me that she will drink wat she needs. she is growing perfectly she is on the 95th percentile for everything and weeing adn pooign like crazy so i guess it is just somethign u have to put up with.