help me my little dog has learned bad habits from my mothers dog.?

the thng is my mothers dog when we were lil girls we did wat most children do tht we thought at the time was funny we would tease her with her toys or tease her by trying to take her chew bones away now its been 7years later and sassy my mothers will come after u if u make tasty noises or attack anything near her when there is food involved now my lil jake which is a jack russel and shihtzu mix very loving and sweet lil guy but we all hve noticed i guess from sassy attacking him tht he is picking up those bad habits of attacking his play mate chia which is gentle as a feather never aggressive but he is being mean to her we may thnk its bcus she is an attention hog when we love on him she will try to squeez in between him and who ever is giving him hugs and attention wat should i do im so lost on these three problems is it me or am i not doin something rite please hlp i want to correct these problems realy soon ty.

What You Do Is Serarpae Them And Quit Teasing Then