McKellen's Lear is so tottery, closer and closer to capsizing in every scene.
If your tottery ancient parent wants to go to Paris, which you feel that they will not survive, they should still (to my mind) be supported in their wishes.
Thereafter, Churchill slid inexorably downhill, getting feebler, deafer, more tottery.
We now have Moira's mother, who was living alone in an Edinburgh flat and becoming increasingly tottery, living with us.