Find Ancestors

I am trying to locate any member of my maternal Grandfathers' family. He was George Frederick Evans, born Cardiff 1897,died Cardiff 1959. His Father was James, from Chard, Somerset b.1862, his mother was Ann (a midwife) b.1870 in Bridport, Dorset. They lived in Treforest, South Glamorgan, when their first child Elizabeth was born in 1892. They were living in Cardiff at the time my Grandfather was born, he was their second child b.1897. There was a second son Harry, born late 1900 or early 1901. They had a further three children another boy and two daughters, names and details lacking on these three. My Grandfather George Frederick married Nellie Bladen from Cardiff, and they had three daughters, Phylis, Doreen (my Mother) and Dorothy. He also served in WW1, in the cavalry, he was caught in a blast and sustained shell shock, which left him with a stammer. From my memory as a child of him, he smoked a pipe and I believe he worked at a power station. I would be grateful for any information as I am trying to compile a family tree and I find I know very little about the Evans side of my family. Unfortunately any one who could have given me any information has passed on.