When My Left Foot became a literary sensation, one of the many people who wrote letters to Brown was married American woman Beth Moore. Brown and Moore became regular correspondents and, in 1960, Brown holidayed in North America and stayed with Moore at her home in Connecticut. When they met again in 1965 they began an affair. Brown journeyed to Connecticut once more to finish his magnum opus, which he had been developing for years. He finally did so in 1967 with help from Moore, who introduced and administered a strict working regimen, mostly by denying him alcohol (on which Brown was dependent) until a day's work was completed. The book, titled Down All the Days, was published in 1970 and was inscribed with a dedication to Moore that read, "For Beth, who with such gentle ferocity, finally whipped me into finishing this book..." During this time, Brown's fame continued to spread internationally and he became a prominent Celebrity. Upon his return to Ireland, he was able to use proceeds from the sales of his books to design and move into a specially constructed home outside Dublin with his sister's family. Though Brown and Beth had planned to marry and live together at the new home, and though Moore had informed her husband of these plans, it was around this time that Brown began an affair with Englishwoman Mary Carr, whom he met at a party in London. Brown then terminated his affair with Moore and married Carr at the Registry Office, Dublin, in 1972. They moved to Stoney Lane, Rathcoole, County Dublin (now site of Lisheen Nursing Home), to Ballyheigue, County Kerry and then to Somerset. He continued to paint, write novels, poetry and plays. His 1974 novel, A Shadow on Summer, was based on his relationship with Moore, whom he still considered a friend.