Definition of “dredge sth up” - Learner’s Dictionary

dredge sth up

phrasal verb with dredge us uk /dredʒ/ verb [ T ]

to talk about something bad or unpleasant that happened in the past:

The newspapers dredged up details about the singer's unhappy childhood.

(Definition of “dredge sth up” from the Cambridge Learner's Dictionary © Cambridge University Press)