2Bedroom/ 2 Babies

Good morning~ We currently have a 23 month old toddler and we want to try for a second..

We live in a 2 Bedroom co-op and I’m not sure where we would put our second.

Of course, our newborn would sleep in our room for the first 3 months, (We sleep trained our first when he was only 3 months old) but how do we arrange it when they’re ready to sleep train?

I’m afraid my toddler’s sleep would be disrupted if we put them in the same together. If anyone has any insight / experiences they would like they share, I’d greatly appreciate it🥰