Your descendants are your children, grandchildren, and so forth. If you have them, they are sitting at the table at breakfast time. Say "hi" to them and ask what their names are. Ho Ho Ho. Your ancestors are probably who you mean.
http://ssdi.genealogy.rootsweb.com/cgi-bin/ssdi.cgihttp://ssdi.genealogy.rootsweb.com/cgi-bin/ssdi.cgi has 91 people named McCann who died in Oklahoma. That would be a place to start. You could also ask your living ancestors - parents, aunts, uncles, grandparents, etc - about the family. Records will always be there; fond memories and old family anecdotes will not.