Sands was born in 1954 to Roman Catholic parents, John (died 2014) and Rosaleen (died 2018), who were both raised in Belfast. After marrying, they relocated to the new development of Abbots Cross, Newtownabbey, County Antrim, outside North Belfast. Sands was the eldest of four children. His younger sisters, Marcella and Bernadette, were born in 1955 and 1958, respectively. He also had a younger brother, John (born 1962). After experiencing harassment and intimidation from their neighbours, the family abandoned the development and moved in with friends for six months before being granted housing in the nearby Rathcoole development. Rathcoole was 30% Catholic and featured Catholic schools as well as a nominally Catholic but religiously-mixed youth football club (an unusual circumstance in Northern Ireland), known as Stella Maris, the same as the school Sands attended and where the training was held. Sands was a member of this club and played left-back. There was another youth club in nearby Greencastle called Star of the Sea and many boys went there when the Stella Maris club closed.