Providing for one's father's new wife and her children

Q: My father has married a young woman who has brought three young children with her and a grandson. My father does not work and he is almost seventy now. He has no pension whatsoever and his only source of income is the money me and my siblings give him. This is his third marriage. The first was to mother who passed away, he got divorced in the second marriage and he was living with my elder sister until now. Then he got married and decided to move into the unfinished house we were building for him. The question is, me and my siblings do not have well paying jobs and still we tried our best to care for him but now he has brought a woman and 4 children that will need support from him. As a Muslim, is it my duty to care for his family? It was already hard to care for him alone and just how are we going to manage taking care of 6 people including him and his wife? Will Allah Ta'ala be angry with us? Because when we send him money now its never enough and we also have our own lives to care for.

Separation and faskh

Q: Me and my wife are currently separated but not divorced. We have been separated for 6 weeks now. My questionson are as follows

1. How long are we allowed to be separated before our marriage is null and void?

2. My wife wants a fasagh however I want to reconcile. The problem was that I borrowed money from a friend and never told my wife and she only found out afterwards that I borrowed money from a female...is she allowed to be granted a fasagh on the basis of mistrust and lies?

3. If she insists for a fasagh and I dont want to because I still love her and for the sake of the children, can the Alim force her to give me a chance even though her parents don't want her to take me back?