Ankles and stabilizer muscles can be strengthened.
One of the best ways to do it is to stand on one foot for as long as you can trying to not support your self with your hands.
It really only requires (at first) slightly lifting one leg and briefly standing the other one for as long as you can.
It is necessary to be in a place and ready to grab something should you lose your balance.
A physical therapist told me one of the best things to do is what kids do. Walk on a curb. She said it’s GREAT PT.
My mom is using ankle weights aroudn the house hoping to strengthen her legs and get more exercise- she definitely needs better stability though-