Baby and toddler sleep advice

We have a 2 year old daughter and we’re currently expecting daughter #2 in November. The first year of the baby’s life I want her to sleep in the room with us for nursing and for safety purposes.

Our toddler sleeps in her own room in a toddler bed. Her and the new baby will share a room once this baby is 1. I’m worried about that transition when they’re in the same room. I don’t want to throw off my oldest sleep schedule if there’s a crying baby adjusting to not sleeping near my bed anymore. And I also don’t want to make it impossible for my youngest to sleep knowing her sister is in there. So basically I need advice and need to know your experiences if you went through this? Thank you so much from one stressed mom to I’m sure another 🥹