If you are still interested after all this time, I can tell you that Lancelot George Jacob was the son of George Jacob by his second marriage, to Emily Ada Myers. I don't know when or where they married. They had two sons, the other being John Myers Jacob (born 1892). The family, including Ivy appear in the 1891 England and Wales census staying in Weston super Mare along with George's widowed mother, Elizabeth.
I am researching the Myers family and would like to know if there is any more you can tell me about Lancelot George Jacob (he was named Lancelot after his grandfather Lancelot Myers).