a sore point

sore point

A topic that makes one angry or uncomfortable. Whatever you do, don't mention his ex-wife—his divorce is really a sore point with him.
See also: point, sore
Farlex Dictionary of Idioms.

a sore point

or

a sore spot

COMMON You can say that a subject is a sore point with someone or a sore spot for them if it makes them feel angry, embarrassed, or upset. The continuing presence of foreign troops remains a very sore point with these students. Slow job growth is a sore spot for the US President. Note: If you touch or hit someone's sore point or sore spot, you mention a subject which makes them feel angry, embarrassed, or upset. The mention of Jim Kennerly had touched her sore spot. It was clear by his expression that my question had hit a sore point.
See also: point, sore
Collins COBUILD Idioms Dictionary, 3rd ed.

a ˌsore ˈpoint (with somebody)

a subject or matter that makes somebody feel angry or hurt: The tax increases are a sore point with Jake, as he’s going to lose a lot of money.
See also: point, sore
Farlex Partner Idioms Dictionary
See also:
  • sore point
  • sore point, a
  • you've got a point there
  • come to the point
  • come to the point and get to the point
  • come/get to the point
  • get to the point
  • get to the point, to
  • all over but the shouting
  • it's all over but the shouting