Frederick and Maud appear to have had 7 children between 1923 and 1934.
England & Wales, National Probate Calendar (Index of Wills and Administrations), 1858-1966 (at Ancestry, Jan 2014):
YORK Frederick William of 21 Northlands Road Winterton near Scunthorpe Lincolnshire died 30 December 194 Probate Lincoln 28 April 1965 to Eric Kemp solicitor and Charles Derrick Rusling legal executive £1873.