Hi,
Welcome to RoostChat
I found this marriage which shows Charlotte as a widow,
Charlotte RUSSELL Mar Q 1877 Dover 2a 1094
Edwin MCCANN
There is an image of the marriage certificate at FindMyPast,
03 Feb 1877
St Mary the Virgin, Dover, Kent
Edward MCCANN
Age: 36
Bachelor
Private 3rd Battn Rifle brigade
Residence at time of marriage: Lime Kiln Street
Father: Michael MCCANN, Shoemaker (deceased)
Charlotte RUSSELL
Age: 32
Widow
Residence at time of marriage: Lime Kiln Street
Father: Charles CHAMBERLAIN, Plumber
I don't know which websites you have access to, so don't know if you can research this info.
I can see some more about who I think is Charlotte but you might enjoy finding it yourself first
Can you give some more details about their children so we can help more and try to find them later on.
It's late here so I have to go, I'll check back tomorrow
Regards,
Daisy