Find Ancestors

A am trying to trace the Griffiths family that was living in the London area between 1800 and 1900. My grandfather was George Griffiths, born in the Kensington district in April 1849. George had a twin sister, whose name I believe was Emily. She apparently died at around the age of 20. They were the children of Stephen Griffiths and Charlotte Wilkins/Day, who were married at St James's, Paddington in 1835. Charlotte's maiden name was Day but she had married a William Wilkins in 1825 and had then been widowed. I can find no trace of Stephen Griffiths (born I believe in 1809) on the IGI. Charlotte was probably a year or two older, and there are various Charlotte Days on the IGI but I've no way of knowing which is correct. I gather Stephen and Charlotte had at least one other child, and I have found a Matilda Griffiths, daughter of Stephen and Charlotte, christened at Clapham in 1836, and on the 1881 census a Stephen Griffiths, born 1809, living in Faroe Road, Fulham, by this time a widower, and his daughter Sarah, aged 34, who has a son called Stephen Griffiths, probably illegitimate. George Griffiths was also a widower when he married my grandmother, Ada Baker, in 1903. I can find no trace of his first marriage or whether there were any children from it. Any information to help with this puzzle would be greatly appreciated. Sue Edwins