Playing or fighting?? I CANT TELL!!

SO it has been about two months now since I brought my new kitten home to my 2 year old cat Hollie. Since then Ivy, the kitten, has gotten alot bigger and I think she is trying to test her boundaries with Hollie. Before they would chase each other and occasionally swipe at one another but now, Ivy will tackle Hollie to the ground and they will make angry noises. I haven't heard any hissing though or grunting or growling. There has never been any blood drawn or fur flying, so I cannot tell if this is real fighting or just playing...or are they just establishing a new hierarchy. I am thinking that Ivy is challenging Hollie for her position in the home. IS this the case? Ivy is also EXTREMELY jealous of any attention that we give Hollie. Thankfully, Hollie would rather not be petted (she has always been that way) but when my boyfriend or I have the chance to pet Hollie we do, but Ivy will come running up to her and chase her away. My boyfriend said that the other day when he was petting Hollie, Ivy came up and actually bit her, not hard but enough to make her meow and run away. Does anyone have any experience with this sort of thing? SHould I just let them work it out or should I try to intervene? Please help!! Any and all advice is greatly appreciated!!

I have the same problem with my two kittens. Jumpy is the alpha male and has always been one so initially Daisy will just go away but she then recently tries to fight back, but this only happened twice that I know of. When Jumpy tries to bully Daisy, I give him a time out by moving him away from Daisy and ignore him. However, I don't give my attention to Daisy either cause I'm afraid Jumpy will get even more upset. I'm just thinking in terms of what human emotion would be like.

The two still tackle one another down and sometimes makes loud noises (never hissing, etc). I know they are just playing with one another because one will be standing right over the other cat who has his/her tummy facing up. If they ever get too rough, I just break them up but minutes later, they go about tackling with one another again.

I do my best in giving them equal treatment. I do believe certain cat wants more attention and be the top cat in the house. I guess it is up to the owner what should be done to bring peace in the house. Good luck!

Kirra and Tiffy do this, though you will hear growling and hissing but never a fluffled tail(well unless Tiffy sneaks up on Kirra, she is a scaredy cat) but the way i have always handled things (i had 13 cats at one point, talk about always vieing for alpha) unless there is blood, teeth are bared, or claws come out, dont intervine. Sometimes its rough play, sometimes its more, but as long as the teeth and claws stay were they should you need to let em work it out/play whichever it is. But do keep some water on hand incase it goes to far.