Well, over the past few days things seem to be getting better with some efforts meant to kind of show her her place in the family. Crate training, not letting her around us when we eat, not being allowed on the furniture, etc. I keep a really close eye to make sure my daughter doesn't get in her face, and I praise all positive interaction between them. If I can tell my daughter is starting to stress Roxy out, that's the only time I let her up on the couch; on the back of it by herself, so she can get up off the floor and away from the loud toddler.
I wanted to post my little update in case anyone else searches with a problem like mine and wants some ideas!