Hi Donna,
Would William's parents - Thomas Mylrea and Margaret Cowin be the couple who married on 7th September, 1809 in Braddan? If so, William's sister - Elizabeth b.1813 was my g.g.grandmother. I believe Margaret Cowin was the daughter of Thomas Cowin and Elizabeth Cottiman m. 9th September, 1780. I am not totally sure of Thomas' parents. If you can give me any help I would be thrilled to bits. I also know that William's other siblings are Thomas b.1815, Philip b.1817, Mary b.1819, John b. 1821, and Ann b.1822. Look forward to hearing from you.
Cheers from Oz,
Billee.