According to The Times, Prince Wiliam’s great-great-great-great-great grandmother was half-Indian.
This isn’t interesting. All humans are related to all other humans, and 7 generations is a long way back.
Also, India didn’t exist as a country at the time William’s ancestor existed (late 18th century).
The Times suggest this may be a reason for William to visit India, presumably because having a tiny amount of DNA originating in South Asia gives Royals the divine right of visitation rights to a former colony. A former colony that, famously, became a republic upon independence and rejected the notion of hereditary monarchs (if not politicians).
As good a reason as any to join Republic.