First of all thank you to Annie & Sarah for helping me get started on rootschat!
Annie you asked me why I think that Mary Ann Cassidy was William Carr's(Kerr) sister. I have a letter from Mary Anne's son which was written inn 1895 to the wife of William, Eliza, stating that his mother, lived at 12 Tern St. Ballymacassett and that she was 70 yrs. old. He also stated in this letter that William has 2 sisters, his mother and Jennie and one brother Hugh.