[AngelBunny]

I think Isis is doing what she's doing--being a Cujo on a leash because you're letting her. You aren't being emphatic enough in putting a stop to her bad manners.

Rottie bitches generally mature around 2 yo. If Isis had nice manners where other dogs were concerrned up until fairly recently (and it sounds as tho she did) and her manners aren't nice any more (and they most certainly don't sound like they are), I think she's turned into a butthead because 1) she maturing and she's not a sweet puppy any more and 2) you let her get away with bad manners.

I think you need to come down on her very hard and make it perfectly, 100% clear that you will not tolerate her being anything but a lamb on a leash and that she will be corrected hard for any infraction. As soon as she settles, throw a party complete with yummy treats. Since Isis is a Rottie, she'll figure out in no time that it's so much nicer when she behaves around other dogs because you're sooo nice to her and Cujo if she doesn't.

It's the old carrot and stick.

Our youngest dog is bitch intolerant and she regards small dogs as prey. I've been on Mox's back her entire life (she's abt 8 yo now), reminding her it'll be a very bad thing if she doesn't mind her manners. I show her in performance events, so it's highly important she doesn't act on her tendencies.