Holiday sleeping arrangements - is this okay?

[CrystalPalace1]

My parents have booked a villa abroad and invited me and my son (15 months old) to go away with them and my siblings. I don’t live with my parents anymore but the rest of my siblings do as they are all school age.
Obviously super excited to go away with them all, but I’ve just asked about the sleeping arrangements to be told that there are only 3 rooms: 2 doubles and 1 with 2 single beds. The villa sleeps 6 plus a baby (I.e. can provide travel cot) but my son has never slept in a cot and we co sleep as he wakes up to breastfeed still.
My parents have said I can choose to share one of the doubles with my younger sister who is 12 years old or have the other room with my sister and that will mean sharing a single bed with my son.
AIBU to think this isn’t going to work? Feel like it’s unfair on my little sister as she will have her sleep disturbed and also unfair on me and my son having less space to sleep.
I really want to go but an anxious about it all tbh now.

I would think it's unlikely your baby will wake a 12yo if he wakes and can immediately get comfort from you. I would go for the 2 singles. Push bed against wall to fence him in.
12yos sleep pretty soundly generally

I’d share a single bed with your baby. Mine is the same age, and we’ve just shared a single bed (twin room, so DP had a single bed too). It wasn’t ideal, but it was fine. If you’re used to cosleeping, you’ll be used to your baby being close to you all night anyway?

If it is mega hot I would have the cot erected anyway next to where you are sleeping as your baby might sleep ok in it

Thanks all. Will go for the singles then. And yes I’m used to him being close to me all night but I also like my space 😂

@AlanJohnsonsBeemer yes will try put him in the cot at bedtime and bring him in to bed once I’m going to sleep. As I’m gonna worry about him falling out in case he rolls over.