Thanks for all your rapid responses.
For clarification - yes, my father-in-law is trying to avail of the 7-year clause so that his children do not have to pay inheritance tax on their father's estate. He plans to put his children down as co-owners on the house deed along with his own name. So they would all be 1/3 owners of the property in the North.
I agree that a first time "buyer" is not the same as a first time "owner". However, in a sense, the house in the North could be seen like a gift since it is not a purchase. Regarding the reciept of a gift of a house, the revenue site says A gift of a house received after the June 2000 is regarded as a prior purchase and would preclude a person from claiming the relief.
However, an inheritance is not regarded as a previous purchase and the first time buyer relief can be claimed provided all other conditions of the relief are satisfied.
Not all that straight forward to me, but if anyone else has some clearer insight in the matter, I'd be grateful to hear it!
[broken link removed]