First off, I would get rid of the bottle. There is no reason any child should be going to bed WITH a bottle, it's a bad habit to get into and it's horrible for their teeth! It's your house so your rules and just because 'it's what mom does" doesn't mean it's what you have to do. I actually don't even do bottles for kids that age at all. when they come here at 12 months they go straight to a sippy cup. Second...she will get use to the new routine of sleeping as soon as she gets there and making it until your nap time. I would let her sleep until about 9 as long as she goes down for the afternoon sleep good too. Third...it's very important that the parents are on board and have the same sort of parenting views as yourself or it won't work very well. Maybe talk with the parents about a routine and seeing if they'd be willing to put her on your routine. If they aren't willing to make any effort on their part, I'd get rid of them.