In September 1912, Brett sailed to New York aboard the RMS Campania in advance of his wedding. While talking to a New York Times reporter, he said that he "knew nothing about the wedding arrangements except the date, and did not even know who was to be the best man. None of his friends, so far as he knew, was going over to the wedding, as the distance was too far. It was suggested that in these days of fast liners the distance was short. He answered: 'It is to English people.' He smilingly denied that the absence of friends from the station implied family opposition to the marriage, and added: 'Why should there be?'".[9]
On 1 October 1912, the then Hon. Oliver Brett was married to the American-born Antoinette Heckscher (1884–1967) at Wincoma, the country home of her parents in Huntington on Long Island in New York.[10] Antoinette was the daughter of German-born August Heckscher, who made his fortune in zinc mining with the New Jersey Zinc Company before entering the New York real estate business.[11][12] Her paternal grandparents were Johann Gustav Heckscher, a German politician who was the Minister of Justice in the provisional German government headed by Archduke John of Austria, and Marie Antoinette (née Brautigan) Heckscher.[13] After their marriage, the couple first made their home at Orchard Lea, Windsor Forest,[10] until acquiring the Watlington Park country house in the Chilterns in 1920.[14] Together, Esher and Antoinette were the parents of:
Lord Esher died on 8 October 1963 at which time he was succeeded in his titles by his son, Lionel. His widow died less than two years later, on 22 July 1965.[2]
Arms
Coat of arms of Oliver Sylvain Baliol Brett, 3rd Viscount Esher
Crest
A lion passant Gules charged on the shoulder with a cross botonny fitchéee Or and holding in the dexter forepaw a fasces Proper.
Escutcheon
Quarterly 1st & 4th Gules within an orle of crosses botonny fitchée Or a lion rampant of the last holding in the dexter forepaw a fasces erect Proper 2nd per pale Or and Gules three leopard's faces counterchanged 3rd Azure three bears' heads couped Argent muzzled Gules.
Supporters
Dexter a boar sinister a lion both Sable and each charged on the shoulder with a cross botonny fitchée Or and holding between the paws a fasces erect Proper.