Hi Rex,
I have attached an extract about Tom from a book that was passed to me from my Grandfather Charles, also a photograph from the book. It looks like from your facts that you may already have seen this as there are a lot of similarities.
Tom was Married to Margaret Brown, Toms Mother was indeed Janet McIlquham, His Father John. Toms Grandfather was William Wood a farmer from Drymen and his Grandmother Elisabeth Risk.
I live just outside Glasgow. Is your Son-in-law any relation to Tom ?
regards
David.