rear its (ugly) head
US /rɪər ɪts (ˈʌɡli) hɛd/
UK /rɪər ɪts (ˈʌɡli) hɛd/

1.
de kop opsteken, weer verschijnen
if an unpleasant situation or problem rears its head, it appears or occurs, especially after being hidden or dormant for a period
:
•
The old rivalry between the two teams began to rear its ugly head again.
De oude rivaliteit tussen de twee teams begon weer de kop op te steken.
•
Whenever we discuss money, his true colors rear their ugly head.
Telkens als we over geld praten, steekt zijn ware aard de kop op.