Newts are cute little animals that can be rewarding to care for without the complications of some pets, although of course they come with their own demands and challenges.
I think they tend to win people over with their little faces and curious personalities. And looking after a pet can be a big boost to someone's quality of life, happiness, etc.
Things to ask yourself are: Is your mother the type of person who appreciates these qualities? Is she capable of doing regular water changes? Does she have access to newt food?
It's great that you're thinking of your mother's well-being. Good luck!