creep up on
US /kriːp ʌp ɑːn/
UK /kriːp ʌp ɑːn/

1.
acercarse sigilosamente, sorprender
to approach someone or something slowly and quietly so as not to be noticed
:
•
The cat tried to creep up on the bird.
El gato intentó acercarse sigilosamente al pájaro.
•
Don't let problems creep up on you; address them early.
No dejes que los problemas te sorprendan; abórdalos temprano.