Some of my friends or their mates are frail. Babies seem fragile. "Frail" is "easily broken" and "fragile" is "easily broken, too. I am wondering whether a 2 yr old or a 98 yr old needs the most care. I realize that most 98 yr olds have had a driving license but now cannot drive. I am confident that not a single 2 yr. has ever driven a car. The 98 yr old may know that he used to drive and he may be in a bad mood about no longer being able or legally allowed to drive.
If the elder is losing mental capacities, especially if they come and go, he might think that he can do some electrical work or use a hunting rifle when in fact he can't successfully. The 2 yr. old would not normally have any idea about electricity or guns but that doesn't mean of course that he isn't going to tug on the trigger or put a metal nail file into a wall socket.
I have not had much intimate care duties of a 2 yr old nor any at all of an elderly man. I can see similarities between a little kid and an elderly man in both behavior and care needs. The baby may just explore everything continuously but the elder may get ideas, notions or irritations that propel his behavior or speech.