My 2 x g.grandmother Alice had 6 brothers (11 siblings in all) and they all used the same pool of names, Hannah, Elizabeth, Margaret, Peter, Mary Ann, Alice, John, Samuel, Thomas, Frederick and William. It was quite a job sorting out which child belonged to which brother. Fortunately, I contacted and was contacted by 3rd cousins descended from each brother and between us we managed to find which child belonged to which brother. Without that input, it would have meant buying lots of birth certificates, or ignoring my 2 x g.grandmother's siblings and their families.