I'll start by saying I am more than happy to be told iabu and will take on any advice given.
So the situation is, my sil is due to go be induced in a couple weeks time with her second baby. We're having dn 2yo as we're the only local support. Plus he is lovely and we don't get to see him as much as we'd like. The problem is he has never had a night away and has coslept from birth. He really finds sleeping in any other arrangement very stressful from what I've gathered from sil. She is quite cagey about it though and this is from reading between the lines. Mil has strong opinions on cosleeping so sil feels awkward about it so she always keeps vague with the details. I personally don't really care how they sleep as long as they get some sleep.
I've been asking for months for a rough plan on what sil needs to be feeling good about the plans as obviously she will struggle being away from him. I've also been asking for months to have dn for occasional sleep overs so he can get used to idea. Every time this has been met with vague and dismissive responses, so I haven't pushed as she seemed uncomfortable. Now a few weeks from the day, sil wants us to have dn from the lunch time the day before till she is discharged from hospital. This could be days and I really don't think it's fair on dn. I suggested I come pick him up very early on the induction date take him to mine in PJs and feed him breakfast at mine so she's not stressing on the day about him. But she's really unhappy with that and now ignoring me. I understand she won't want her dp to leave while she's waiting to go into labour so he doesn't miss it so we will obviously have him for the nights of the induction without complaint. But I think minimising the stress for dn is also a priority. I don't want him struggling with being away for days, then his baby brother appearing which will be difficult for him as it is. I'm happy to have him as long as it takes for her to have the baby, but the extra night the day before seems to unnessicairy. Aibu and awkward? I've never been induced or heavily pregnant with a toddler so I really wouldn't know.