[SunkenCiv]

Given her era, it’s possible. :^) But I think the Hapsburgs were known for receding chins, due to generations of consanguineous marriages.

[Joe 6-pack]

"But I think the Hapsburgs were known for receding chins, due to generations of consanguineous marriages."

To the contrary, they were known for pronounced chins as a result of generations of intermarriage...

[x]

You may have been thinking of the British aristocracy.

Noun chinless wonder (plural chinless wonders) (Britain, derogatory) An ineffectual upper-class man, typically dim-witted and of a weak or indecisive character, frequently one who gained his position through nepotism or social connections.