Preauricular sinuses (ear pits) are common congenital abnormalities. Usually asymptomatic, they manifest as small dells adjacent to the external ear near the anterior margin of the ascending limb of the helix, most frequently on the right side. Preauricular sinuses can be either inherited or sporadic.
Are preauricular sinus harmful...
The main problem with preauricular pits, if they appear in an otherwise healthy child, is that they can lead to benign cysts or infections, including small pus-filled masses known as abscesses. When a child gets repeat infections, a surgeon may recommend complete removal of the pit.
I only heard about it while working on a ENT/ Maxillofacial ward as part of my student adult nursing.