Our experience with little dogs in with the big dogs seems to be that some can handle it and some cant. The little ones that cant just scream bloody murder if a big dog comes anywhere close to them. Then their owners usually pick them up... ahh in the arms of their owner, safe and sound. There was a Corgi at the dog park this past Sunday that Treo was real interested in... and boy did he SCREAM. She didnt even touch him... if any one came up to smell, he just let loose. Eventually he got comfortable... but man, I though Treo was being mean there for a minute!

I understand worrying about her.. because I worry about Bunny and her prey drive. She and Zeke attacked my would be SIL's toy poodle.. had to get stitches in its head. (Of course this was after we told her not to bring it out with our two!) So I know Bunny has a prey drive, and its usually triggered by Chihuahuas. We keep a beep/shock training collar on her the whole time at the park and just beep when she's being inappropriate.

I think it sounds like Delta is fine... and it sounds like you do the best you can to keep her in line. Really all we can do is keep socializing them and they'll continue to learn whats a toy and whats another dog. =)