The two boys were
Ernest Jones - aged 11 in 1911 and his brother Albert - aged 9.
They are the sons of William Hopwood Jones and his second wife Edith Maria Matthews. William died in 1907, and Edith then married Henry Waterhouse in 1913.
The 1911 census shows the two boys at Styal Cottage Homes, whilst Edith and the two daughters were living in West Gorton.
The relationship with Alfred Evan Jones is via William Hopwood Jones, who is the father of Alfred Evans's mother, Frances by his first wife, Ellen Tomlinson.
Ooh - just realised that I have Ernest on the 1921 census as Ernest Hopwood Jones aged 21 as stepson with Henry Waterhouse and Edith Maria.