In Rise Up Women: The Remarkable Lives of the Suffragettes published by Bloomsbury mention is made of Sophia providing cakes for the WSPU shop in Shrubbery Road, Streatham.
"..a new WSPU shop opened in Streatham run by honorary secretary of the branch, Leonora Tyson, who had also been running Lambeth WSPU. The window in Shrubbery Road was tastefully dressed in colours. There was an abundance of sweets and cakes for the opening party- some donated by Princess Sophia Duleep Singh- but the cost of renting and decorating the shop had been used up all their funds. Leonora Tyson asked members if they could donate any unwanted furniture such as writing tables, paper baskets, a bookcase, a coal-scutlle, doormat and chairs. Like all the WSPU shops, Streatham sold postcards and badges, scarves and muffs and pamphlets and canvas bags for selling copies of Votes for Women"