Wiktionary
poor relation
n. Something seen as inferior.
Usage examples of "poor relation".
If I had been her secretary, steward, half-brother, poor relation –.
Lily had no mind for the vagabond life of the poor relation, and to adapt herself to Mrs.
Thrifty, who is good, wise, just, and owes no man a penny, turns from a beggar, haggles with a hackney-coachman, or denies a poor relation, and I doubt which is the most selfish of the two.
It is because Stepmama treats you like a poor relation and encourages the impression most of the guests have that you are your grandmama’.