General Disgrace:
* The black sheep of the family: This refers to someone who is considered an outcast or a misfit in their family.
* To bring shame on the family name: This implies that someone's actions have negatively impacted the family's reputation.
* To be a bad apple: This suggests that someone is corrupting or damaging the family unit.
More Specific to Disgrace:
* To be a disgrace to one's heritage: This focuses on the idea that someone is dishonoring their family's history or traditions.
* To make the family name mud: This implies that someone has significantly damaged the family's reputation through their actions.
Other Expressions:
* To be a disappointment to one's family: This emphasizes the feeling of letdown and frustration that the family might feel.
* To give the family a bad name: This highlights the negative impact someone's actions have on the family's image.
The best idiom to use depends on the specific context and nuance you want to convey.