Michael Cashin, Ballinakill, served in British Army until 1812

My 3rd ggrandfather, Michael Cashin (alias Cashen according to his military papers), was born in Ballinakill c1782. He joined the military in 1798 and served in the 22nd Foot Regiment and for a while in the 12th Royal Veteran Battalion. He was discharged as an out pensioner in 1812. There are no additional papers in his file until 1846 so there are many years missing. I don't know if he returned to his home or not. There don't appear to be any Cashens or Cashins in Ballinakill at the time of the Tithes or Griffith's. Perhaps the family moved nearby. It seems a bit early for anyone to have emigrated. His daughter Eliza was born c1820-1822, perhaps before most Baptismal registers were kept. I am not sure where she was born, nor can I be sure that Eliza's father was married when she was born. She emigrated to England, probably in the mid to late 1830's and married. Her father spent one year with the family before he died in 1851. I would be interested in finding other members of this extended family and learning more about Michael's family. I realize my chances are slim. Thank you.