I haven't read the book Victoria and Abdul by Shrabani Basu, but recently viewed the movie version starring Judy Dench as Queen Victoria and Ali Fazal as Karim Abdul.
Because there was great jealousy of Queen Victoria's relationship with Karim Abdul, whom she called her son in letters to him, her family tried to burn every remnant of him after Queen Victoria died and evicted him from his home on the Queen's estate and sent him back to his hometown in India. The story came to light 100 years later when journalist Shrabani Basu discovered a bust and paintings of Karim at the Queen's summer home on the Isle of Wight. After further research where she found journals written by Queen Victoria in Hindustani located at Windsor Castle, Ms. Basu found that it was Karim Abdul who had taught the Queen the language and become her confidant and friend. Historians had dismissed the journals and their contents because they were not written in a western language.
There are mixed reviews of the movie, but I found it intriguing and humorous at times and Judi Dench is such an accomplished actress that her portrayal of Queen Victoria was brilliant. Joined with Ali Fazal, they both filled the screen with their friendship and admiration for each other.