The problem should not be allowed to fester.

Time only allows the suspicion of injustice to fester.

Don't allow anger to grow and fester in your heart.

My wounds fester and are loathsome.

Frustration will fester at the kingdom.

Does a dream deferred fester like a sore?

The deadly biohazards fester in the DNA of the plants and animals.

Such beliefs will be left to fester.

The knee wound is now festering.

This will create a lovely place for rot to live, fester and raise its ugly head.