You might like to check out the following:
1841 census. John Cubbon c1817, Lead miner, wife Margaret c1820. Residence: Glen May, Patrick. Son Richard is aged 2.
1871 census. Same family still living in Glen May, Richard now aged 30, single, a lead miner and unmarried, so eligible to marry.
If there's a marriage cert for Richard and Charlotte then it will likely confirm or deny the connection above.