Were a lot of the male heirs in royalties poisoned at young ages, seems like in countris with turmoil they di?

Question

Were a lot of the male heirs in royalties poisoned at young ages, seems like in countris with turmoil they di?

Answer 1

Maybe not poisoned, however, a lot of "male heirs" were known to be born with extremely poor health, and were constantly falling ill. I suppose when the country is going through crisis, the young heir's proper care was overlooked. The affect of stress, tension and fear can all be fatal  especially to an ill-health youngster.

Answer 2

In which country?  This may have happened a long time ago, but nowadays, there are very few absolute monarchs, and their heirs would be well protected, how many "spares" are needed in these days of modern medicine?