Sft - you need to order Ivy's birth cert to find out.
The info isn't available online - you need to order the cert from
http://www.gro.gov.uk/gro/content/ 
The family are definitely down as Milne in 1901, and the children are recorded as being Lois' (William isn't living with the family):
1901RG13/2976 7 6
Loughborough, Leicestershire
109 Storer Rd Lois Rebecca Milne, head, mar, 28, b. Leicestershire Leicester
Ivy Blanche do., dau, 9, b. b. Belgrave
William Christmas Louis do., son, 8, b. Loughborough
Louis Welfred Gladstone do., son, 6, b. do.
Frederick Victor Harcourt do. son, 3, b. do.
Did you find Louis' registration in the name Newick?