To tell my husband to stop saying this?

Cats are for everyone. Your DH is sexist and needs to realise that boys and men also like cats. Look at the many cat dads on social media.

Women are reclaiming the historic trope of crazy cat lady, and that's a very good thing.
Here's a nice podcast episode for your husband to learn he's being sexist.
https://www.bbc.co.uk/sounds/play/m002hksl

Can't believe people are falling for the tropes of advertising. Ignore any sexist Amazon labelling. They label all Lego as being for boys and/or for girls, even though Lego largely stopped using those stereotypes years ago.

It’s a black and white shorts and t shirt set with an animal on. How are they feminine ?!

also worrying your DH thinks that hot pants that show bum cheeks are for young girls

Yes, I agree. Really odd.

I called off my wedding for less! Your DH is being an arsehole and is bullying your son. It needs to stop.

Bloody hell. He’s 9 tell
your husband to leave him alone. It’s just PJs ffs

Unless he’s Mr Popular and invited to sleepovers constantly then he’s showing a lot less at home than girls do in swimsuits in public.

Is it just these pjs your husband doesn't like.
If your son had different pair would he be complaining about something else ( hair style, TV shows, hobbies) your son likes.
PJ issue will pass soon he will grow out of them or need a warmer long leg pair for winter.
But issue is doubt your husband attitude to him will improve after pjs

they are girls PJ's so no i wouldn't have bought them for my son.

I think your DH is right but maybe not delivering the message as subtly as he could given your version of what he says.

Says me. My opinion. I never said it was a "fact".
Any more than your opinion is "fact".

If I'd seen these pyjamas online without anyone saying anything to me first I'd have assumed they were marketed toward boys. That is, obviously, based on some sexist generalisations of my own: I assume (based on personal experience) that the sorts of girls who want cat pyjamas tend to be very feminine in their tastes, and that any cat pyjamas chosen for them would therefore be made in more feminine colours, with more kittenish cat pictures, and in a more feminine style. I am unsure what your husband means by 'full coverage'. The shorts aren't that short, and anyway, they're pyjamas, so your son isn't going to be wearing them in public. The idea that girls should wear shorter shorts is bizarre anyway. If it's genital peeking your husband is so neurotically anxious about then I'm sure your son will be happy to wear some pants underneath to minimise the chances of that happening (although quite possibly he does that already). Is this part of a wider concern your husband has about your son's preference for cats over more stereotypically 'guy animals' (snakes, spiders, dinosaurs, big scary dogs, whatever) or are these blameless nightwear items the only trigger for his fragile masculinity?

my husband thinks the shorts on the pyjamas are too short. Like little hot pants. Sometimes when son is lounging on the sofa they ride up and some bum cheek is visible. This angers husband and starts him off on his “girls’ pyjamas” conversation again.

The shorts should either be unacceptably short for everyone, or they should be a none issue. The fact that your husband thinks ‘short shorts’ are ‘girl’s shorts’ and are acceptable for girls your son’s age is grim to be honest.

Don’t be ridiculous
Just because your 9 year old doesn’t want them, doesn’t mean that they are ‘girls pj’s,’ it just means that your 9 year old doesn’t like them.
If the OPs son, or any other boy, likes them, then good for him.
The OPs husband isn’t ‘right’ he’s a bully. They are pjs for goodness sake.

Doesn't matter whether they are designed and marketed for girls. Son loves them and his dad is being a cunt bullying him for something that has zero affect on him. Who does he think is going to see him if that's his concern?
How many women wear their dhs t shirts, shirts, goodies etc? No one thinks anything of it.
Bullying cunt.

I’m kind of on the fence with this. I think your husband is right, they are girl’s PJs and if I saw them in a shop that would be my thought. I also agree that any shorts that potentially expose bum cheeks on either boys or girls are inappropriate so I’d look for a pair with longer shorts. I do agree with him if your son was to wear these to a sleepover he may well get teased (children can be so cruel).
Having said that, your husband shouldn’t be continuing to torment your son and needs to recognise that his son likes them and that’s what matters.

Your husband is an ignorant bully who should be utterly ashamed of himself.

They are bits of cloth sewn together - they are pj’s - they do not have a sex or gender - they are clothes which your son likes.

Why is your husband being so nasty to his son?

I wouldn’t stand for it . He would be told in no uncertain terms to stop.

What a horrible, horrible way to treat anyone - especially your own son.

Sounds like he’d be fine with a 10 year old daughter roaming the house in hot pants, just not a son. Which is weird.

How to fuck up a child, 101.

At what age though?

If her son chose these PJs, then that is one thing. He is who he is and there is nothing wrong with that.

It sounds like OP chose them, knowing that they are for girls and acknowledges that their 10 year old son now roams their house in hot pants and wants her husband to be ok with it.

I put my son in his sister's old pyjamas if they have animals on. Unless he asked for that, I wouldn't put him in her old ballerina nighties. Plenty of baby pics of him in floral and pink blankets. I won't but him that sort of thing aged 10 unless that's what he chose.

Etsy have boy cat pj's or why not swop the bottoms so they aren't so revealing, but your husband is bullying

In the description it says girls , so I'm wondering if he has looked them up and is making his unkind words to your ds based on that ?
Tbh if your son enjoys wearing them even if they were bright pink with bows on who cares .

I agree with your DH.

The question I would ask is if your DS’s friends saw him wearing them would they ridicule him. I suspect you know the answer to that.

You then need to decide if you want to facilitate the wearing of such items behind closed doors. That’s up to you and DH but anyone trying to virtue signal about it is being disingenuous. Would you be OK if he said he wanted to go to school in a dress?

Oh sorry, didn't realise your DS had authority on this 🙄🤣

For everyone who's saying "well it says girls so they must be made for girls bodies", they are the exact same pattern as all the "boys" pajamas by the same company.

Op if you bought a pair of the "boys" pajamas with the exact same cut and fit, what would your husband say then?

Agreed!

And the other classic one "Cereal? It's not breakfast time now".

My son is generally either in his work uniform or his PJs and will eat cereal anytime of the day or night.

I would just buy a pair of jersey shorts with longer legs just for the peace. Shouldn’t have to but 🤷🏻‍♀️

Then I would start a conversation with DH about how he is going to react in future if DS doesn’t conform to his view of what he should be