Just trying to make head and tail of it.
So both OH and son have this 5th-8th cousin 1% 9cm 1 segment - so paternal line
Whilst OH doesn't have any shared matches with the cousin - son has 1 shared match but it is a 4th - 6th cousin on his maternal irish side showing 1% and 35cm.
That cousin has a small tree but is mostly American and nothing matches up with any names or areas/places.
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