Kitten sleep advice

Hi! My husband and I recently brought in a 2 month old kitten. We are expecting to get a second kitten soon so she's not alone, but wanted to get advice on sleeping arrangements. As we don't want our current kitten to feel alone, we have her in our room when we sleep, however once we get the second kitten, we want them to spend time together at night. Should we try having her sleep alone before the second kitten comes to get used to being alone while they are getting to know each other, or keep the sleeping arrangement until they get used to each other?

Thanks in advance for your advice :) we want to make this arrangement stress free for both of them!