They are close in age right? Its normal. When we brought Kash home we just watched Hanna to make sure she played with him the right way since he was the little guy. Now they go full force UFC match all over the house. If one yelps, I always make sure they are ok, but if the yelper goes back for more, they are fine.
Here is video the first week we brought Kash home -
They are only a week a part, but very different in size. He weighs 13 pounds at 10 weeks and she weight 8 pounds at 9 weeks. He is also a lot taller than she is. He is lanky, all legs and very very thin, she is short and fat. They do look like they are playing, but I am not sure when to stop them. I know they need to learn bite inhibition and this is how they do that. It just scares me. I don't want them to hurt each other.
They have a blast chasing each other and tackling each other, she's pretty feisty. Is it normal for them to growl a lot and sound vicious?
Oh yeah, they will and should be fine. And Hanna is very vocal it scares me, but her main is down and tail wagging so its ok. Kash, he just goes right in, he's glutten for punishment. He pushes her buttons even though she has 12 lbs on him.
I just say let them go at it, but be right there. If they look too rough for your liking, then just separate for a bit, and maybe use "easy" when you separate. Since they are close in age, they will probablly treat each other like littermates.
I think Mick and Indys mom can be of more insight, she has littermates, I have them 1.5 years apart
Like Heather says, that's all pretty normal...Just wait til they get older!!! Buck & Tia used to sound like they were killing each other, but other than a few scratches, they were fine..Also learn your babies body language, just watch them, you will soon be able to tell what is play and what isn't....To me, there is nothing more fun than watching 2 boxers just having at it, could sit and watch them for hours...