Henry - bap 9 May 1880 Clapham Holy Trinity (Birth Reg, Wandsworth Q1 1880)
Frank - bap 19 Jun 1881 Upper Tooting Holy Trinity (Birth Reg, Brighton Q2 1881) (Brighton given as POB in 1901)
Hellen - bap 7 Jan 1882 Upper Tooting Holy Trinity (Birth Reg, Wandsworth Q1 1883)
Harriet - bap 4 Jun 1884 Upper Tooting Holy Trinity (Birth Reg, Wandsworth Q2 1884)
Mabel - b 27 Jan 1886, bap 14 Mar 1886 West Kensington St Andrew [sorry, not Tooting, my mistake!] (Birth Reg either of 2x female Kings Wandsworth Q1 1886 or a Mabel in Fulham Q1 1886)
Robert - b 16 Oct 1889 bap 20 Apr 1890 West Kensington St Andrew (Birth Reg, either Wandsworth Q2 1889 or Fulham Q4 1889)
Mildred - bap 14 Nov 1891, Walham Green (Birth Reg, Fulham Q4 1891)
transcribed twice on Ancestry as 1891 and 1892 - the register has had these added on after the 1893 dates, so the final figure is a bit unclear but the following entry is also Nov 1891
Mabel King 1901 - aged 15, b Kensington, at King Edward's School [orphanage] , St George's Road, Southwark. Ref RG13, 370, 107, 4
Don't think the 1899 marriage of Ellen King is relevant - there's a John and Ellen Noonan in Fulham in 1901, with 3 months old child. Ellen is 23
By the way - the Selleys and King children are not just in the same street, but the same house! The address on3 Mildred' baptism (and1891 census) is 28 Bramber Road