Congenital melanocytic hairy nevus is a rare dermatological condition that may present in different clinical patterns. We report a unique familial occurrence in which both a daughter (born 2018) and her father (born 1985) were found to have congenital hairy nevi localized on the flexor surface of the forearm. The lesions measured approximately 4 cm in diameter in the child and 2.5 cm in the father. Both patients had been kept under observation without surgical or cosmetic intervention. Familial occurrence of congenital melanocytic hairy nevus is extremely rare, and its documentation contributes to the understanding of possible genetic predisposition. This report emphasizes the importance of long-term follow-up and awareness of such cases in dermatological practice.

Congenital melanocytic nevus; Hairy nevus; Familial occurrence; Dermatology case report; Genetic predisposition

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