Cat and Kitten play fighting

[miccoops]

Hi all,
I posted about a week and a half ago about my adult cat (Leo, 5) and kitten Pepper (10 weeks). Things have really improved but I was hoping to seek some advice on play fighting. So they are now very happy to be in the same room, playing or having treats. We've had no obvious aggression from Leo for a week, no hissing, growling etc.. They are getting very interested in each other and seeking each other out, always supervised.
So they have now moved to what I believe is play fighting. They'll chase each other and Leo makes a sort 'chirpy' sound, a mix between a purr and meow.. usually the noise he'll make when food is around so I'm assuming a good noise? They they sort of stand on back legs and wave arms at each other.. its quite funny as there is a very big size difference. The only thing to check is sometimes it gets bit rough for Pepper and she'll yelp.. at this point I stop and separate and put her back in her base room. They both seem to continue looking for each other though.. am I right to stop at that point? Is it right that it sounds like play fighting.. it does look a bit full on but then Pepper will run straight after Leo..and he isn't hissing or growling, no hairs up or any sign of real fighting..

I should add there has been no injuries from the play fighting. Thanks all

All sounds ok to me. No harm in separating them, it might help just to calm things down if play is getting rough. My two girls play fight and it can get quite physical, but they are evenly matched for size, no one actually gets hurt and then 10 minutes later they're curled up asleep together.

Thanks @Beamur. I think I'm nervous as we had a bit of a rough start, Leo was being aggressive so its just understanding the shift to play fighting.. He has groomed her a couple of times but then goes off and sleeps upstairs, she is being kept downstairs for now.

Cats in a multi cat household need to be able to retreat to a safe space away from other cats sometimes. I think it's probably wise to enforce some time apart to allow their relationship to develop slowly.
The fact that your older cat is being calmer is good, the grooming is a nice sign. Cat interaction is really interesting. So much of it is around scent. The grooming means they are swapping scents which is really positive, cats sort of mark 'their' pals with their own scent (when your cat rubs round your legs for example) so if they are doing this voluntarily they are becoming better acquainted.