Just reading this question another time and I think it’s important for a toddler to signs it’s readu to toilet train. No signs means he’s not ready.
9 Signs Your Toddler Is Ready to Be Toilet Trained
Your toddler is drier for longer.
He can follow simple directions.
Your toddler is showing independence.
He poops on schedule.
He’s interested in the process.
Your tot announces his pee and poop.
Your child doesn’t like being wet or dirty.
Your toddler can undress himself.

Why don’t you try? If he’s not ready, you’ll be able to tell in a few days. In which case, just stop and try again in a few months.

I wouldn’t toilet train as such, but start with getting him familiar to the potty / toilet and take him to the toilet when you and your husband go yourself so he can start copying you when he’s ready. There are some nice books, apps and you tube video’s (like Toms Toileting triumph video) you can read & watch as preparation.

No 21 months is too young especially for a boy. Does not sound like he is ready

I would try, not push. If he is open to suggestion then great he might benefit but worste case you might have to try again when he’s a little older.

You can always give it a go. No harm done

I would say he is too young. how did you go?

I guess it can’t hurt to raise the subject with him and get him familiar with the potty and / or toilet. If he hates having his nappy changed the idea of the potty might appeal to him.

Good luck!

talk to him – he will know how to take his nappy off, ask if he wants to go to the toilet like a big boy – don’t make a big deal of it… Not too many kids are not trained by school !

Leave a potty in the room with him for him to try when he wants. Don’t force him but give lots of encouragement

My daughter’s daycare don’t use nappies after a certain age and toilet train them – I think it is around 2yrs. Earlier if they show interest. I heard the summer before they are 2 as they get wet and there’s less layers of clothing to change. Definitely try and have an open dialogue with him about the toilet. My friend tried to make it fun but getting a themed potty, sticker chart etc

Go for it the earlier better!!!! My lo is older and we are still trying any time after 18 months whenever you and bub are ready!

Ours hated they potty and preferred the toilet with the special seat on it. He was training quite well then suddenly he refused. No idea why!! A few weeks later he showed interest so we started again. Sometimes when we reckon he should go we tell him we are going. Sometimes he says “no, me, mine” We still have the odd little accident if somebody moves his stool that he climbs onto first. I cope with dirty nappies Ok but struggle with dirty pants. His is fairly moist and “sticky” still and is hard to remove the surplus from undies before soaking and washing. He wipes himself but we always help to make sure he is clean. He is allowed to flush the toilet provided he uses it. In the early stages that was a great incentive. Soon he will have to learn to use the toilet like Dad if we are going to travel in country areas where there isn’t always toilets just when he needs one. He hasn’t really learnt to “hang on” like older ones fo.

I’d go for it – definitely worth a try and would save you the hassle of trying to get him to wear nappies when he doesn’t want to. If he is resistant and he isn’t keen you can just give up for now and try again at a later date. Good luck!

might be a little young but def cant hurt to try. have a few nappy free days (bare) and keep the potty handy!