James Edmund was born at 11 Kennington Green, Lambeth, London on 23rd December 1847: his father was James and his mother Sophia Alexandrina née Laycock. He was baptised at St. Mark's Kennington on 20th March 1848. These registers (IGI batch P015571) show a brother Charles Joseph baptised on 10 July 1850 and a sister Sophia Alice baptised on 2nd April 1854. (I believe it was Charles and his family whom Muriel visited in Canada around 1910.) There were also other siblings - see below.
James Edmund and his family are shown living at 93 Lausanne Road Camberwell in the 1881 census: this reveals that they had three children at that time. Gertrude was the oldest at 3, Muriel the next (1) and brother Walter James the youngest at 7 months. They seem to have moved around: Gertrude was born in Herne Bay, the other two in Peckham. James Edmund was a Commercial Traveller (American Corn). James' brother Walter R Osman, who was born in Brixton c. 1857, was also staying: he was a Commercial Traveller (French Upholstery). They also had two teenage servants: Fanny Bedwell from Canterbury and Mary Hoare from Hatcham. There is a slight discrepancy in James Edmund's age - from his birth certificate he must have been about 34 but he is shown as 32.