Puppy's play fighting

Me and my partner recently got a bitch and her sisters ended up getting one of the dogs from the litter. They play fight a lot when together. They don't seem to be hurting each other but it does look a bit rough is this normal ? We have a staff cross which is 7 and they play about with her aswell. The pups have caught her a couple of times and she's let out a yelp and they seem to get a fright and stop. We do intervine if we think it's going to far. We have read that puppy's shouldn't show aggression and they seem to growl a bit when playing / fighting. Is there anything we should be doing or is this just fun for the dogs?

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They are 11 weeks. Not the older dog obviously

Sounds like normal behaviour to me. Staffords tend to play hard. If they stop when your older dog yelps, this too is normal behaviour. If another Pup in the litter yelps when play fighting this is the signal for them to stop.
If they didn't stop at the yelp, I would be more concerned.

The older dog is cross staff but this is the first full staff we have had. My partner already had the older dog before we got together. I'm used to Alsations and tbh if I had 2 of them it wouldn't bother me that they were doing this as I know the breed. My partner wouldn't have one though as she likes staffs. We did research before getting the dog so although not staff pros we knew what to kind of expect

Sounds normal - they're only puppies so it won't be aggression, purely play. As said the yelping is normal (you'll also want to do it if they start nipping/mouthing at you!). Keep intervening when you feel necessary and be prepared for some full-on staffy play ahead of you

Lovely pics   btw   

Here's a link that should help. If you think thingsd are getting out of hand just step in like you already are.

http://staffy-bull-terrier.com/is_my_dog_aggressive

BOdy language takes some time to be able to understand but this should help

http://staffy-bull-terrier.com/dog_body_language

Beautiful pics, and I agree with above, staffords play hard, sounds all normal to me, just keep doing what your doing

Lovely pictures very cute

Thanks for the replys appreciated. Also the males chest there seems to be a bit sticking out that's quite prominent that the female doesn't have. He doesn't look that much bigger in the top picture but side by side there's a big difference. Is that unusual ? Or will he grow into it

you had to see what my younger one did to their mum they just about rip off her ears it's becasue of their pin teeths lol the consistent trainning and over time that will stop

Sounds normal behaviour to me also, just keep with the consistency and stepping in and all will be fine   

They are gorgeous   Staffys do play rough and make crazy noises while doing it!!