I need help with my kittens.

I have a 3 month old male kitten, and a 7 week old female kitten. I've had Rocky for a few weeks - almost 2 months now. I've had Zoey for two days. Everytime I put the two cats together, Rocky grabs onto her and bites her and she yells, really loud like he's hurting her. Now, Chris and I are almost to end of our ropes, because I don't want to have to keep them apart, and babysit them forever. Otherwise we would have had kids I need advice, and I am new to this forum. Everytime we bring them together she runs up to him and hisses at him, and he chases her, and that's when he begins to tackle her and hurting her. I feel bad because this was his house for a little while, but I though that if we got her while he was still young that it would be okay. I don't know if the running and tackling are just really rough play. Please, somebody give me some advice. We did try giving him positive reinforcment everytime he behaves himself around her by giving him treats. Like, when he just sits on the bed and lets her run and play, but what are we supposed to do when he misbehaves? We used to spray him with water, but he plays in the toliet, and likes to go in the bath tub when it's filled up. So please, someone give me some advice. Thank you
It's much appreciated

Amanda & Chris

That's a big age difference for kittens to be together. I would keep them seperated till the 7 week old gets a little older.

i agree, we had a kitten who was 9 weeks old when we had a litter of kittens born, when the kittens were about 6 weeks old (making sophie 15 weeks) she would hiss at them attack them etc. we kept it so they was always supervised , and at night or when we go out we put them in their own room for saftey (not only from sophie ) but from other dangers around the house after a cupple of weeks of supervised vists sophie came around and now there all best of buds the kittens are now 13 weeks old and sophie is 22 weeks old (the kittens get the better of her now while playing lol).
it qill get better you just have to give it time.

Dominance issues here - keep the little one away for the moment like the others said.