Where do your children sleep when they go to grandparents?

So my mom wants to take my 18 month old off my hands this weekend and im totally cool with it I can use a break since baby #2 is due next month. The only thing is we just recently started sleep training her to sleep in her own bed in her own room. For a year and a half she slept my bed with me and my husband. 🤦 finally got her out of my bed and ready for the new baby to co sleep with us. (We learned our lesson lol he will only be in our room for the first few months) I asked my mom where my daughter will sleep at her house and she said with her, in her bed. I'm nervous because i dont want her to get use to sleeping with someone again! My mom still trys to give her warm bottles of milk before bed. When we stopped that at around 13 or 14 months. I feel like everything I worked on my mom is trying to undo it because she still sees her as a baby. Its so frustrating. I'm worried that In return I will have a fussy 18 month old who would want to sleep with me and want a bottle and New born baby all in ny room. Am I over reacting?

My mom said if she cant sleep with her in her bed then she should just stay home with me instead🤷 she doesnt want to compromise.