Assisting one's sister with zakaat

Q: My sister has separated from her husband. She and her three kids are living with my brother and his family (i.e. wife and two little daughters) in one bedroom appartment in London. Her husband has not yet given her divorce but also does not pay for anything for the kids either. She herself is not working at the moment. Can I pay my zakaat to her or it will only be considered as sadaqah?

Sharing YouTube videos with people

Q: I follow the opinion of Shaykh Ibn Uthaymeen regarding piracy where he says: "In my view, if a person copies them for his own personal use, there is no harm in that. However, if he copies them for trade purposes, this is not permissible since it involves causing harm to others."

I use a website to download youtube videos for personal use so I can share them with family. Is this permissible as I know there can be issues with copyright in some countries. I’m from the UK. In cases like this, when does the ‘law of the land’ take precedence over Shari’ah? If ever? I don’t really fear any legal consequences although I know there are copyright laws here.