New fila owner here with some questions. We recently acquired a now 11wk old female. We have had her for one week now (got her at 10wk old) she has a fantastic and sweet disposition very loving, she is also very calm for a puppy in my opinion. She has short spurts of puppy play but 90% of the time is very calm, observant, and seemingly serious. The day we met her, the breeder brought her to our home and she instantly accepted my wife, myself and our 2&5 yro girls with licks and lots of love. She adapted shockingly quick to her new home with no apparent separation issues and has particularly bonded to my wife and I and is always near one of us. The only potential issue we have encountered is, we also have a 10yro step daughter who lives with us 1wk on 1wk off with her father. She was not present when the pup came to our home but arrived 3 days later. The pup immediately wasn’t crazy about her. She always gives her a low growl when she approaches or even just barks at her as she walks through the house. We have been working hard daily to encourage interaction between them with and without us by their side. She had made several snapping attempts at her when trying this. However we have also had productive sessions where she relaxes and plays with her well, let’s her touch and love on her. But then it’s like 30 minutes or an hr later we are back to the growling and barking. Our 10yro daughter is the only person she has acted like this towards and we have introduced her to probably a dozen other people and extended family. Does anyone have any suggestions on exercises we can do to encourage her to bond with her? Things we should or shouldn’t be doing. I realize it’s still early but I want to get this behavior in check ASAP.