This monument was erected by the two daughters of the deceased couple, Sir John Tyrall and his wife Mary. The monument is signed by the sculptor Nollekens but not dated. A manuscript document entitled 'Collections of Inscriptions upon Monuments and under Busts executed by Joseph Nollekens' shows the epitaph for the Tyrell memorial among other monuments dated from the late 1780s and can therefore be also dated from the same period. We don't know the reason why the daughters commissioned the monument to their their parents twenty years after their death.

The coat of arms and inscription record them, while the draped urn is a standard Classical symbol of death. Two cherubim are depicted at the base, but Christian imagery is subdued, as is commonly the case with British Protestant church monuments.

Nollekens was a prolific sculptor of portrait busts and operated a thriving workshop in London. Many of his busts are in the classical style, with loose drapery and cropped hair. He spent eight years in Rome from 1762 to 1770, where he worked with Bartolomeo Cavaceppi restoring and copying antique marbles. One of these copies, his group of Castor and Pollux, is in the Museum's collection (Museum no. A.59-1940). On his return to England he became the leading sculptor in London, and was quickly overwhelmed with commissions. One of his former studio assistants, J. T. Smith, was to write a vituperative biography of the sculptor after his death, in which he condemned him as a miser, ridiculing his odd personal habits and the squalor in which he lived. However, he admitted that Nollekens worked exceptionally hard, and that his portrait busts in particular were unrivalled.