Hi Lillian,
Thanks for your question. Catherine Martin (Obed's second wife) is my 3rd great grandmother through her 2nd marriage (Joseph Singleton m 1860 in Ireland). I was not aware that Catherine and Obed had children - or at least I have none recorded.
I am happy to share information with you, most of which has been gathered by my Mum (Glenys Arnold).
The tree goes:
Rick Chadderton
Glenys Arnold
Lois Hobson
Ellen Miranda Fletcher
Elizabeth Jane Singleton b abt 1860 County Down, Ireland
Catherine Margaret Martin
I hope this helps.
Regards, Rick Chadderton