Margaret Riley (née Platt) was the wife of Tom Riley and mother to Mavis.
Despite both being teetotal, Margaret and Tom ran an off-licence in Grange-over-Sands - having moved there from Weatherfield following Mavis's birth. In 1971, Mavis left the town and returned to Weatherfield to work at the Mark Brittain Warehouse. She returned to the town for three months in 1974 after receiving a lack of commitment from her then-boyfriend, Jerry Booth.