on 1900 and 1910 census, there are four children - Fredrick, Ralph, Alice, and annie, all b. Calif.
John b. Ger says he came to US 1880 or 1888 depending on which census, and naturalized in 1885
Bessie came to US 1887 (1920)
1900 they had been married for 10yrs. so I'm guessing they were married in US, unless you found the registration in England.
1881 england census Essex, Brentwood School Alice Tilley, 14, says b. Hackney, Middlesex (but, all students (or inmates as they are called) are listed as b. in Hackney. Annie Tilley, 12 F.James Tilley, 10 Bessie Tilley, 8
Looks like she named her daughters after her sisters.