The person to contact is Avron Cohen he has the most complete family records and just returned from Latvia and Lithuania where he discovered new information. His email address is
avronc@exemail.com.au. He is in Sydney Australia. It does sound like there is a good chance you are related in some way as most of the family changed the name from Kagan to Kahn or Cohen. Some of the family did end up in England (some in Ireland) and many in South Africa. He is your best chance to locate a connection if there is one. All the best in your search. Life is Good David