Edmund is born in Sirhowy, Bedwelty.
On the 1851 census the address is Scybor Wen (Mary Ann is born here too in 1864)- we find Mary Edmunds, head, widow - Ann Plumber, daughter, married - Edmund Plumber, Grandson - John Plumber, Grandson + a lodger. So from that I deduct that Mary Edmunds is the mother of Ann and Grandmother of Edmund and John.
Gwen