The Royal arms are those of Princess Sophia, the fifth of the six daughters of George III and Queen Charlotte. Queen Charlotte was protective of her daughters, attempting to shield them from marriage, and limit their suitors.
Princess Sophia never married, though she did form an attachment to Major General Thomas Garth (1744-1828). In 1800, she bore him a son named Thomas (d. 1875), who Garth raised at Weymouth.
After her mother's death in 1818, Princess Sophia lived at Kensington Palace in Vicarage Place and became a close confidante of the Duchess of Kent, Queen Victoria's mother. Princess Sophia and the Duchess formed an alliance with Sir John Conroy, who eventually embezzled most of the Princess's money.
Following her death in 1848, Princess Sophia's jewelry and silver was valued by Garrard's at £6,728 2s 6d, and divided in four parts. The remaining plate was sold by Garrard's in 1848 for £1,012 17s 6d. Vicarage Place and its residual contents were sold by Christie's, 1848-1849. (See Jane Roberts, ed., George III and Queen Charlotte, Patronage, Collecting and Court Taste, 2004, p. 388.)
H.R.H. the Princess Sophia (1777-1848), after Sir William Beechey