Jonathan Hiatt Nicolson Dermot Irwin (21 June 1941 – 10 December 2023) was a British-Irish bloodstock agent, auctioneer, stud owner, publisher, racetrack executive and charity founder.

In 1997, he founded the Jack and Jill Foundation[1] with his wife Mary Ann O'Brien, to provide home health care to severely sick babies.

His father, John Irwin, was an Irish actor, writer and a BBC producer and his mother Philippa Hiatt, was a British stage and screen actress.

[6]: 62  By his second term at Trinity, his interest in racing had begun to overshadow his studies, when a friend of his mother's, the ex-Battle of Britain pilot Wing Commander Tim Vigors, asked him to join his Dublin bloodstock agency at IR£5 a week.

[10] During his time with British Bloodstock Agency (Ireland) Limited, he introduced the Irish Stallion Incentive Scheme which was so successful that it morphed into the European Breeders Fund.

Irwin forged a number of international connections and was largely responsible for the development of the highly lucrative Japanese trade in the late 1960s and early 1970s.

With a £100 capital and the floor of his flat in Fitzwilliam Square for offices, he and two friends started the magazine to fill a gap in Irish publishing and, having got it on its feet, he sold out to the Farmer's Journal.

[11] In 1974 Irwin was approached by the Irish senator and racing patron Paddy McGrath to manage Goffs, then a small private company on the verge of bankruptcy.

I was in Australia when I heard the news that the R.D.S., whose Professor James Meenan had earlier given his blessing to the Kill project, had executed a volte-face and were back in contention.

Thereafter there was no great problem[tone] in raising the finance but the group of underwriters had certain reservations[clarification needed] about the existing management structure in Goffs.

Thus Irwin replaced Robert Myerscough as managing director of R.J. Goff and Co. Ltd. on 1 January 1975 and oversaw the construction of the world's first purpose-built bloodstock sales complex in Kill.

Due to complications shortly after birth, Jack developed severe brain damage, which left him without sight or hearing, and unable to swallow.

[13] The family suffered significant trauma, and encountered a series of bureaucratic obstacles before an offer of help from a retired nurse provided a catalyst which sustained them through the remaining months of their son's short life.