Relatives of Hannah Mohan ne Devin/Duane

Hello everyone, 

I am searching for any family connections, past or present, to my ggg grandma who hailed from Knock and Corohan townland, Dunmore parish ,Galway. She married Michael Mahon in 1836, had 4 children, Mark,Margaret, Sabina and Patrick before leaving for England around 1849.

I have been unable to find a baptism record for her, guessing she was born around 1820 at the latest, but unsure whether they existed at that point? 

Hoping for another branch of the tree 🤞

Thank you for your time. 

Dawn