I am also researching the BIGG family from Herts. My gg grandfather John BIGG was born in Watford to John and Sarah BIGG (formerly Collings) They lived in Beecher Grove Watford in 1841/1851 and he was a carman. I am certain they had other children (poss William b 1832, Martha, Mary Anne, James who I think dies in 1843 aged 1 and Sarah)
John Bigg junior moved to Islington after marrying Emma Sutton in 1867 and had 8 children (William John, Emma Kate, Henry J, Ada, John Thomas, James, Albert and Minnie Rebecca)
William JOhn the eldest child is my g grandfather. His youngest son, Charles Albert Bigg born Islington 1905 was my grandad.
I believe many of the ealry BIGG family events were focused around St MAry's Church in Watfford and I hope to go to view the parish records soon.
Does any of this sound familiar?
Keep in touch. The BIGG family sure does seem BIGG!