Hello, everyone!

I'm new to the world of Cavaliers. We actually adopted a Sheltie, who we thought was spayed, but in fact was pregnant. Her puppies, determined by a DNA test (which I believe is accurate based on they knew nothing about the mom being Sheltie) determined they were half cavalier/half Sheltie. There is other stuff mixed in but I'm here to determine if these behaviors one of mine is experience are cavalier-like and how to work with them. We kept two puppies and one acts a lot like a Sheltie... the other is totally different than what I'm used to.

When we go on walks, she has the strongest prey instinct and wants to get anything that moves. It's not herding, because she's caught birds before and killed them. She actually, oddly enough, has no virtually no herding instinct. She wants to get bunnies, squirrels, cats or anything small that moves. I thought she wanted to play until the day a baby bird decided to let her four babies learn to fly in our yard and she caught two of them, immediately killing them. She is good with my cat, but she was born at my home and been with her since birth. She hasn't tried to hurt another cat, but I wouldn't trust her around one most likely that she didn't know. So anyway, on walks, she's a handful. Her eyes are scanning around the whole time looking for things and prepared to chase. She gets very upset when children are playing and moving quickly. She basically barks and pulls at anything moving. I was able to train her out of cars/bikes, or she outgrew it, but the main issue is birds on walks and then people (but I think people might be another issue where she just needs to feel more comfortable that I'm in control.) My boy has none of these issues and turned out basically perfect in terms of behaving well on walks. He has no interest in things moving and just walks along happily. I feel like my girl, Lily, has the highest alert senses and her smell is amazing... she will smell or sense an animal way before I see it! she walks with her head down sniffing the ground most of the time. It's so different than what I'm used to with my shelties, and could really use some help. I'm not sure if this is just dog behavior and has nothing to do with cavaliers as I really don't know much about this breed. I've always admired them, but never owned one or looked into one.

Thanks for the help and suggestions on how to deal with her prey instinct... She's clicker trained, but I can't seem to get her to let go of that alertness she's always on.