Should I Be Worried Options

[Ashantay]

We have a border collie called Kissa she is 9 years old and the top dog in our pack (underneath me and my husband of course). Recently we have been dog sitting the smallest jack russell I have ever seen. She is a year and a half and approximately 5 or 6 pounds I have seen rats bigger, our Kissa keeps following her and pushing her down with her nose and I can see her getting a bit excited like maybe she is something to eat and I worry... Yesterday while outside she kept pushing her down with her nose then turning her by nudging her in a circle. We are a bit concerned that she is going to try to eat her or something but at the same time she shows no aggression towards her in the house so do not know if we should be worried. We are watching closely anyway because she is our friends dog but if she is in any danger we do not want to sit her again as we would hate to see anything happen to her.

[Penninepoodlewelfare]

Sounds like she thinks the jr is her puppy

"I dont remember giving birth but this is obviously my puppy"

[FeeFee]

It sounds as though she's 'herding' her. It doesn't sound aggressive, but the other dog may get fed up with it and object, so personally I'd be discouraging it and distracting your dog to do something else when you see it happening.

[nikirushka]

What is the rest of her body language like? Relaxed? Happy-waggy (decent speed, not crazy-fast or very slow)?

What she's doing sounds very much like how my Opi (rotti X) will play with a lot of dogs these days - and how she used to play with my sister's chihuahua when she saw him often. It's entirely an effort to get them to play - she does it every time we run into the JRT X I used to dogsit - but with her it can be quite forceful so for safety, she's not allowed to poke small dogs

With Monkey (the chi) she was very gentle, it was lovely to see Normally when she plays she leaps about like a thing possessed, mouths, GRARRS and boxes btu with him she would lay down and just nudge him with her nose. He never appreciated it mind you

[mollies mum]

My bitch kept doing this when my kittens were little, she'd pin then down and then she'd want to wash their rear end, I think she wanted to mother them but she was quite rough or at least I thought so even though the kittens weren't bothered, but as she was doing this she'd get over excited.

[Ashantay]

yea that is what she is doing and we were wondering because she is quite excited when she is watching her and she ONLY does it outside and watches her and kind of tries to keep her close to us... obviously the little dog being an adult herself does not care much for it and we have discouraged the behaviour. Fortunately she goes home tomorrow but I think we would be ok to watch her again. Kissa has/had great mothering instincts when she went through her false pregnancy as far as watching over her squeaky went and nesting and stuff so maybe that is all it is.

Thanks for the replies guys I appreciate it a lot and from what you guys have said I feel confident that she was not trying to hurt her.