[2] In due course Sarah became housekeeper to William Thwaytes, who was by then the sole owner of Davison, Newman & Co. and a wealthy grocer and tea merchant.

[2][4][5] On 19 May 1816 Sarah Hook married Alfred Tebbitt, Thwaytes's chief clerk, at St Martin's in the Fields, Westminster.

In 1832, during her husband's last illness, Ann developed a mental disorder which began with "low fever" (a 19th-century term for murine typhus) and a subsequent nervous state in which she remained for ten weeks facing the wall whilst believing she was blind.

[6] She recovered from the fever, but nevertheless declared that she was "immortal and part of the Trinity," and that she and the couple's family doctor John Simm Smith (1793–1877) had "important work to do.

[2][5] William Thwaytes's Will makes her a "joint executrix and main beneficiary" and describes her as his "beloved wife" in spite of her earlier suspicion that he was poisoning her.

Soon after the funeral she was befriended by Simm's brother Samuel; he was a stockbroker whose wife had died, leaving him with two daughters and a debt of £3,000 (equivalent to £364,205 in 2023) which Ann paid.

[11][2] The 1851 Census finds her at age 63 staying at her town house with her Charmandean lodger Samuel Smith, a butler, footman, three housemaids, a cook and a kitchen maid.

[15] She added an iron-framed conservatory, and two pairs of wrought iron entrance-gates made as replicas of the former Buckingham Palace gates.

[2][10] She died aged 76 at her London town house in 1866, and was buried on 13 April in a vaulted grave at Broadwater and Worthing Cemetery, in plot C4.1–4.10–13, near the North Chapel.

It was during this case that the unmarried situation of Ann Thwaytes's mother came to light, because illegitimacy might put Sarah Tebbitt's position of rightful heir in doubt.

He said, however, that if she had been found to have been in sound mind, there remained the question of possible undue influence by the Smith brothers, putting the validity of the Will doubly in doubt.

During the full moon at Broadwater she was observed by worried neighbours to dress in white and to drive the same route in her yellow carriage ritually: past the old Sussex Pad Inn (now replaced with a hotel), over Old Shoreham Bridge, and back home again.

She would talk to her friend Louisa Little, her niece Mrs Cook who noted Ann's sayings in a diary, and to servants and tradesmen, about her religious beliefs, but would close the discussion if rebuffed.

Secondly, following the expansion of the middle classes in the 18th and 19th centuries, beneficence was "an avenue for entry into elite society for women and gave them a sense of place and direction outside the home.

Kentish Gazette, 23 August 1836[3][23][24][25][26][27] In the address which was read to her when she laid the foundation stone, some of her good deeds were enumerated: The poorer inhabitants, the labourers and mechanics especially, will gratefully acknowledge that to your unexampled liberality they are indebted for many of their past comforts, for their present employment and for the education of their children.

After the Clock Tower had been opened, builder George Burge began work on the old St John's Church in Brunswick Square.

Around 1839 to 1840, Burge informed Mrs Thwaytes that if the Clock Tower's bricks had been available for the building of the church, St John's would have been completed "long before."

This project was started by her friend and consulting surgeon Dr Frederick Dixon who had founded the local Worthing Dispensary in 1829 and treated poor patients for free.

Dixon was an amateur geologist who died young, and Ann funded his book, The Geology of Sussex when it was published posthumously.