A type of being The Un-Favourite in which a character's parent compares them negatively to one of their friends or acquaintances. It is very common for this to sow antagonism between the two people compared. The extent to which the parent shows this attitude tends to vary, ranging from an unconscious preference for the friend to an openly antagonistic attitude towards their own child.
In these situations, the parent will usually employ some variation of Why Couldn't You Be Different? against their child at some point, telling them that they should try to be more like the person they are being negatively compared to.
Contrast Like a Son to Me, which generally has much more positive connotations.
Compare "Well Done, Son" Guy.
Why Are You Not My Son? has been suggested to play 2 roles. Click below to see other actors suggested for each role, and vote for who you think would play the role best.