Lady Kitty Spencer is reportedly converting to Judaism months after announcing her engagement to fashion tycoon Michael Lewis.

Lady Kitty Spencer, niece to Princess Diana, is taking "religious instruction" to convert to her fiancé's faith, reports The Sunday Times quoting a friend of her.

While it's not yet ascertained which of the three branches of Judaism she is committing to, the 29-year-old has been spotted attending synagogue, house of worship for the Jewish community, with her would-be husband in London.

According to the outlet, the conversion will require her to observe the Sabbath- the bible of the Jewish faith, as well as follow Jewish dietary laws that include cutting out pork and shellfish.

Leola, the first wife of the South Africa-born multi-millionaire with whom he shares three children, had also converted to Judaism before getting married to him in an orthodox Jewish ceremony back in 1985.

Kitty Spencer, daughter of Charles, the 9th Earl of Spencer, is first cousin to Prince William, the Duke of Cambridge, who is a future Supreme Governor of the Church of England and second in the line of succession to the British throne.

The supermodel said yes when the chairman of Foschini Group, who is 32 years her senior at the age of 61, proposed to her before Christmas last year. Their relationship first made headlines in August, when they were spotted kissing after leaving a club in St Topez and then again when it was discovered that Lewis is five-years-older than Kitty's father and his children are older than Kitty. It is believed that the couple has been dating since August 2018.

lady kitty spencer
Lady Kitty Spencer Getty

Although Kitty will soon be stepmother to three adults, she earlier revealed that she is not planning to start a family anytime soon. In an interview with Mail Online, she said: "I can see myself having children at some point. But I'm only in my 20s. I do have my friends my age who are having children, and they are so, so sweet, but I think everyone should do things in their own time."