I agree, Carole, this is probably him in 1901:
1901 census: 3 Dearden St, Hulme
William DOWNING, Head, M, 30, House Painter, Lancs Manchester
Emily DOWNING, Wife, M, 29
Mary J. DOWNING, Daur, S, 11
Emily DOWNING, Daur, S, 9
William DOWNING, Son, S, 6
Harriet DOWNING, Daur, S, 8
Benjamin DOWNING, Son, S, 4
James DOWNING, Son, S, 1
Zachariah MELLOR, F in Law, M, 57, Shoemaker, Lancs Blackburn
Mary Ann MELLOR, M in Law, M, 49, Lancs Manchester
All children born Manchester