Relationship that brokeup and got back together

[Rotating Rabbit]

So my sister and her boyfriend broke up around january of this year mainly because they were arguing on where in the country they wanted to live (ie he wanted to move, she didnt,though im not sure this is the whole of it obviously). Anyway they just got back together and she's all happy about it etc. None of us particularly like this guy cos hes a douchebag and my father is particulaly unkeen on him but obviously she doesnt let that influence, so it goes and i guess my parents were secretly happy when they broke up (aside from seeing their daughter upset etc). So what are the chances of them sticking and if so how long in oot's experience?