playing or fighting?

I got a new female rat to put in with bonnie. I introduced them in a neutral spot and everything was fine. they where together for about 2 hours.

Today, i went to switch around tanks so I put bonnie in with Lily (the new juvi. female) together while I cleaned the tanks. Well, I looked over to check on them and Lily was jumping all over bonnie and "attacking" her neck. bonnie kept rolling over onto her back but Lily kept "attacking". i took bonnie out until I got answers.

Please help, I just want to make sure everyone is safe.

They do have to establish a pecking order and may fight to determine who it the boss. I'd keep an eye on them and seperate them if blood is drawn.

My younger male will often bounce on my older male, and he's just playing. As long as they aren't squeaking and there is no blood, I'd say let them go at it.

that's normal dominance squabbles. squeeking is ok. As long as nobody seems to be getting hurt or drawing blood, I'd let them go for it.

the only thing is the little one is urinating on the older one, ewww.

also, when the older one goes to groom or just sit with the little one, she rounds on the older rat. hmmmm