Here it can also help the partner in case of inheritance.

For example, if you haven't lived together for over 3 years and aren't married, then unless there's a will the partner won't inherit anything. If you have a kid, the kid will get most of the inheritance but can't manage the money until they're 18.

Been a few cases in the media here where the kid inherits lots of money on a locked account while the partner that's left struggles to make ends meet.