Hello! We've just bought a charcoal lab and would like to breed him. I have a female silver that I am interested in, so I have asked for pedigrees. On the pedigree for the female I noticed that there is a dog that is her great granddam (?). That same dog is a great great granddam for our male. Is this a problem? How far back do I need to look on a pedigree? Thanks for any help!