I have a 21 month old, and he sleeps fine. We did a very modified Ferber at about 5 months. However, whenever I give him an inch, he takes a foot... To give you an example, at 10 months he decided he wasn't going to let me leave the room until he fell sleep. From 10 months to 18 months I stayed in the room while he was going to sleep. up to 15 months I would actually have to stand over his crib and rub his back, and from 15 to 18 months I sat in the chair while he fell sleep. What changed at the end was my patience. I was spending up to an hour just sitting there, and it was taking longer and longer every night. It started with 5 minutes at first, so it was harmless to stay in the room for 5 minutes; BUT AN HOUR!!!! in any case one day when he turned 18 months, I told him that Mommy was going to sleep as I put him in the bed and left. He cried and cried and I had to ignore it. He cried for about 15 minutes and fell sleep, and the next night 5 minutes and no more crying after that. I don't like to hear him cry either, but I really think the not liking to hear him cry hurt him more than if I just did it. He wasn't getting a good night sleep, and he was starting to wake up in the middle of night crying because I wasn't sitting in the chair. Now, he is all smiles when I put him in his crib, and loves going to sleep. I put him in and kiss him and say i see you tomorrow and that I love him. I think you just have to stay strong, and remember what the goal is. If your baby sleeps better and is better rested, I think it may be worth letting her cry a little bit. I'm not for letting her cry it out, I wouldn't suggest leaving her in the room to cry for long period of time. You know your child, and how long she can go for. Read the Ferber book, I didn't follow it exactly the way it said but tried to figure what my son really needed. So I went in more frequently and stayed in the room a bit longer. All I can say is the earlier you deal with the sleep issue he easier it is. It gets harder the older they are. Good luck.