Thank you everyone who took the time to write with advice! I really appreciate it. The ideas, the reassurances, and reports from your babies helped a lot. My baby is doing really well now. She has figured out her sippy cup and is wanting to eat and drink everything all by herself now. After a few days her drinking is back to normal. Sometimes they just go through a lot of changes all at once and it can be hard to know if it is normal and will even out, or if you should be concerned (and this even with my third child!). I should add that she weaned herself. I had tried to get her to breastfeed and she will have none of it. She graduated from baby to big girl all at once! Thanks again for all your help. Moms are the best.
T.