Thanks for the added information. I have just relocated the following info which may help clarify the Schmitt children. (from my confused earlier filing system

)
According to the St Georges Lutheran Church Records they had a child baptised on 23/12/1855, 09/05/1858, 03/06/1860 & 07/12/1862. .
So they must have been in England since 23/12/1855.
I have Gustave's marriage certificate to Elisabeth Kirschei, 25th October 1868, at Church Of St Boniface, Mile End Old Town, Middlesex, a German Catholic Church. Witnesses were Peter Smith and Wilhemina Smith. Celebrant was A.D. Purcell, RC Priest, John B. Ratcliffe Registrar.
Another family member found that Wilhemina was formerly a Vander Velden( many different spelling variation used by each of the 9 of Gustave's children, and for different occasions for the same children). I have copies of many BMD cert for the children, including Mary, my maternal grandmother.
Distant family connections have given me a more detailed ancestor line of Elisabeth Kirschei, but Gustave's background draws a complete blank, except his marriage and census docs state place of birth as Nassau. His father is given as Henry Vonderfelten, carpenter.
Cheers
Sandra