ABSTRACT A 2-weeks-old Saudi neonate was apparently well till the 10th day of life when a swelling of the right groin was noted accompanied by irritability and fever, without history of trauma. On examination: the girl was irritable and febrile, the mass was firm, ill defined, fixed and tender. The state of the underlying skin was normal. There was family history of 3 siblings with similar swellings in the neonatal period and one of them had recurrence of the condition till the age of 7 year. The radiological findings indicated diaphysis hyperostosis, sparring of the epiphysis and the benign course of the disease. With exclusion of syphilis, osteomyelitis and trauma, the likely diagnosis would be infantile cortical hyperostosis. Such diagnosis should not be overlooked when faced by bony swellings in neonates