Angelina
To summarize it,when Emilie stay at my parents' home,she's not supposed to masturbate(but still do it),and we don't want to propose them the idea of having her wear a chastity belt "permanently" while at home(even for making her allowed to stay more often),as it would prevent her to masturbate too,and as we would not be able to make my parents remove such rule easily after it is applied.
I probably would ask soon,with Emilie;there probably would be a talk,and maybe some more rules,and we would decide what to do,considering these rules(if there is any).