Here is my 2 cents on how to change your child's sleeping behavior. My son (now 2 1/2) is a beautiful sleeper & stays in his bed all night long without waking us up. I promise you, that was not the case for the first 17 months of his life! He used to wake me up at LEAST twice in a night to retrieve his pacifier & blanket he would throw out of his crib. I used to feel bad for him and thought he wouldn't be able to fall back asleep without his pacifier if I didn't give it to him, so I would go in there and give in every time. My husband and I finally got fed up with it after so many interrupted nights of sleep and decided to do the "necessary" and stop going in his room when he cried. Deep down inside we knew that we were reinforcing this behavior and the only way to change it was to give him a clear message that his behavior is not correct when it's time to sleep. I think you would probably agree (as would your pediatrician) that your child does NOT need milk at night due to hunger & it could also cause cavities in her teeth from the sugar sitting on them all night. She is playing you for attention - that's all. :)
Here's my advice:
The best way to get your child to stop waking up all night is to stop responding to it. Every time you go in & give in to the undesired behavior, your reinforce it. I learned this quickly with my son when I stopped responding to his negative behaviors. He realized that my husband and I did not support what he was doing, so he eventually stopped since it there was no more reason to wake up. I recommend waiting until a weekend to work on the change (if no one works then.
This plan worked the best for us and is the overall simplest (but not emotionally):
When she cries, do not respond. Do not go in her room. Let her cry it out. It should only take a few days, but she will learn that no one is coming in her room anymore and will get the message that there is no point in waking up anymore. It took my son approximately 3-4 days, then suddenly: NO MORE WAKING!!! It was beautiful!!
If you want to do this gradually (and I mean not more than a few days of this), then try this:
First time she cries, go to her room and state (in the dark without picking her up) "It's night night time. Mommy and Daddy are sleeping and you (her name) needs to sleep, too. Goodnight - I love you". LEAVE THE ROOM!
Second time (after she finally settles back down from the first time because she will cry since she's used to you coming in there & giving her milk), just state "Night Night Time". LEAVE.
Third time - DO NOT GO IN! :) It will seem very painful, but let her cry it out. Do this for any subsequent wakings.
I am not saying this will be easy, but who ever told us parenting would be easy? :) I just told myself that this will be the first of many times I have to take charge of the situation and do what may be emotionally hard for me, but what is ultimately best for our child. Don't feel guilty or worried that she is hungry - as long as you have fed her her normal meals in the day, she will be fine. It won't take as long as you think and you will look back on this and say "why didn't I do this earlier!"
I wish you all the best of luck. Be strong about it and don't go back on your old ways once you decide to do it.