Highly recommended to get FIDO keys. Assuming you get multiple keys - and you can even share one physical key as a back up key across all family accounts, while

Highly recommended to get FIDO keys. Assuming you get multiple keys - and you can even share one physical key as a back up key across all family accounts, while each person has one personal key each - and register each phone as another fido key, and cross register parents keys with each other's, and for children's accounts. That way, every account will have at least 4 keys, with different physical exposure. The chance of lock out is basically 0 at that point. Added bonus is that security key auth don't need most of the heuristics based phishing or credential theft detection applied, as they are provably unphishable. So the sign-in is less likely to be subject to false positives of heuristics.