Advice on Sleeping Ideas for My 15 Month Old and 3 Month Old

Hi L.,
I am a preschool Special Education teacher and have just started a new business, It's Aparent. Your 15 month old should be weaned off of the bottle at bed time and on to a cup. If she is drinking the bottle in bed, she needs to be weaned now, because milk sitting in the mouth will rot her teath, and cause her to loose her baby teeth prematurely. I have seen it in my students too many times to count. These children then have difficulty talking because they usually are missing their top two to four top and or bottom teeth.
Take all of her bottles, put them in a bag and let her walk them to the trash can so that she sees they go bye bye. Then let her help you purcfhase new big girl cups. They can be sippy cups that will later turn into a regular cup. Never put a child to bed with a bottle.
Once she has transitioned successfully from the bottle to the cup, you should wait a few weeks before you move her little sister into her room. Wait until she is asleep then put the baby in her room. If you are using the crib that belonged to your older daughter, disguise it with new beddidng so that your older daughter doesn't feel like she is being pushed out of her bed.
Don't forget to make sure that you spend plenty of alone time with your older daughter. We tend to get caught up with the new baby and forget that the older child needs individual time without the baby around with both parents.

Hope this helps,
F.

It's best to get the toddler used to the idea that she has to share the room she will adjust to having the baby their and that might help them bond as sisters.

First, I would advise making transitions one at a time, with at least a month or so between them. I would start with transitioning your 3 month old to her sister's room first, then worry about the bottle later. We transitioned our 3 month old into her brother's room (he's two) a few months ago, and it went very smoothly. I was worried that they would wake each other up, but they just tune the noise out. In the two months they have only woken each other up maybe once or twice (when it's screaming or tantrum time, really extreme noise). I started by having her take naps in his room every day, and "talking up" the fact that now he had a great roommate and didn't have to sleep in his room by himself anymore. After about a week of that, I started putting her down to sleep in his room before he went to bed, so he could see the process and know what was going on. It went really smoothly. Toddlers are more flexible than we think. Good luck!

You might want to try putting on some soothing, very soft (barely audible) music in their bedroom, something on a loop that will play throughout the night (my daughter only seemed to sleep to Jerry Lee Lewis, and Ray Charles!) but really soft jazz or even better classical would give them something to self soothe to.