Best PJs for very cold nights - wool/thermal?

[Nightnight23]

We’re off to my in laws at the end of October. They live abroad and whilst it’ll be hot in the day it will be 4-6 degrees overnight and they have no central heating so it’s going to be cold overnight. I want to get some really snuggly PJs for my 2 year old - do I fork out on some wool ones (which I don’t mind if they’ll keep him snug) or are thermals better? I know you can get fleece style ones from primary’s but are they as warm as other options? Any advice appreciated.

Proper flannel is best, I think.

And take a hot water bottle

Marks and Spencer's do Childrens thermals - that might be an idea - you could buy the top and leggings and use them as pj's

www.marksandspencer.com/l/kids/kids-thermal-and-ski

The solution for a camping holiday with those kind of temperatures was a fleece onesie (with feet!) over normal pyjamas.... there are loads around. Flannel wasn't warm enough although merino was great (very expensive though) but with the onesie they didn't get cold especially if the covers fell off etc. and there are loads on eBay if they aren't in the shops yet.

Do they not have any heating at all in the bedrooms? We dont have central heating (not in UK either) and it can get down to 0 sometimes in the winter at night, and we have plug in oil radiators which help. If not, we find a few layers of blankets help. We also have bed socks!

Flannel pyjamas are very popular here, and I know quite a few kids wear thermals underneath them. Ds1 does this when it is really cold, but the others get too hot. Either that or onesies as a pp said.

Thanks everyone. Some great ideas.
No they don’t have any central heating at all. It’s actually just my MiL now as FIL passed away and SIL’s now all moved out so she has a stove in the room she sleeps in that she keeps stoked up throughout the night. I don’t fancy us all sleeping in the same room though for two weeks
My husband said he’d get an electric heater but I just don’t like having plug in heaters in the room my son is sleeping in over there as I don’t trust the electrics - I don’t think they’re up to our standards.
Hot water bottle is a great idea too.
They have lots of wool blankets which are actually soooo heavy as they’re essentially duvets stuffed with a tonne of wool but I could actually put one between DS and the mattress to keep him snug too.
Ironically I’m also wondering whether I’ll need suncream in the day as it could get up to 26 degrees