Hi,
New on here but I know the Michael Read Mason / Maria Rebecca Mohun connection as they are ancestors of my late husband.
They had one daughter named Hannah Rebecca (possibly Hannah Elizabeth Rebecca in one census).
I have the marriage and death certificates for Michael Read Mason but I have got a bit of fog regarding Maria Rebecca Mason nee Mohun after 1861 census. Doesn't help that her brother's second wife was also Maria and was born in the same year.