Sibling Rivalry?

Hi

I have two 6 month old brother and sister combo. I have only had them a couple of weeks, but we have bonded fabulously, especially my boy (excuse me for not using a name, I haven't fully hit on them yet, keep changing my mind...) Anyways, the little girl has started being more friendly and coming to me. Not EVERY time she does, but most of the time, her brother comes and butts in and even bites her. I know he bites for play too, and doen't mean harm, but I am wondering if he is also marking territory. Will this stop? I have told him no a few times, cause I want her to now stop coming to me. We are all getting along so well.

It's a domination act, he is telling her to back off and wanting to get all of your attention. I would take her into another room and shut the door and play with her and bond with her about 10 minutes a day, solely one on one, do the same with him as well.

Thanks, that makes sense.