N.M.
My advice is not to stress too much about it. It may not be as big a deal to them as you think it will be. I never had a problem getting my children to give up the bottle. I did the switch at about a year. With my daughter, 4 yrs., was a little concerned that it might be a problem because my friends had told me about their experience with it being difficult. I began with one switch a day. I think it was the morning since she was hungriest then and would be more likely to take the cup. I then moved on to the other bottles throughout the day. I did the bedtime bottle last. It only took a week to do the complete move to sippy cups. However, I had been doing water and watered down juice in the sippy cups for a few months already. I used the kind that were very similar to bottles first, I think they were Nuby. I went mostly by the age recommendations on the cups. That said, I did not let her ever go to bed with a bottle. I always held her in my lap in the rocking chair at night. Once she finished I would lay her down. She did use a paci, so I think that helped satisfy the "suck for comfort" need. With my son, 2 yrs, it was even easier. I was expecting problems with him because he seemed more attached to the bottle than my daughter was. However, at a year I just went straight to the cup. One day I just stopped the bottle completely. My doctor recommended I try it because there may not be a problem at all...and there wasn't. Again I had been using sippy cups with him for water and juice for a few months. So it wasn't totally new to him. I used the same cups I had with my daughter. Now he uses open cups and the cups with straws. I did the same thing with him at night that I did with my daughter. When they moved to cups, I would let them have a cup right before bed at the table. No cups in their rooms. He also used a paci, though. Again my advice is not to stress about this. Bottles can be a pain to wash each day, but sippy cups aren't much easier. Also, don't let society or pressure from others dictate when your children should do things. I am guessing that no matter how attached they may be now...they will move to cups before kindergarten.