William Russell

I am looking for information on my 4 x Ggrandfather, John Russell. From my records he was born about 1790 Curraghmulkin, Tyrone, Ireland  and died 1867 in Omagh, Tyrone, Ireland. He married Mary Glen. His son William Russell, 1813-1877? was born tyrone Ireland but have no record of his death. He married Rebecca Jane Lietch 1815-1865. William and Rebeccas son, William 1848-1906 immigrated to Australia I think in 1864. This William married Margaret Fowles 1857-1923 in Roma Queensland Australia in 1876. I am really at a loss with any more information on John Russell. Hope someone can assist me. thanks Debbie Ayres