Perhaps someone can explain to me exactly what the connection is between 'natural law' and a legal provision to enable someone to continue to live in his/her home after the death of his/her partner? Or to visit that partner in hospital? Or to have time off from work to look after him/her at home? Aren't these things not simply 'human rights', but common decency? Not according to the pope, they're not.
As Jeremy Bentham said: people invoke Natural Law when they wish to get their way without having to argue for it.
'Natural law' is a cultural construct, honey. Even in Latin. Live with it.