In a royal family where scandal seems to rotate among its members with nearly metronomic regularity, one might have predicted that Tuesday’s news of Prince Andrew having settled a sexual abuse lawsuit against him would soon be followed by a fresh, troubling disclosure about another royal.

Sure enough, not 24 hours later, London’s Metropolitan Police announced an investigation into allegations that a charity led by Prince Charles had offered to help with a knighthood and British citizenship for a wealthy Saudi in return for a donation. A spokesperson for Charles insisted that he had no knowledge of any deal.

For Queen Elizabeth II, it's been a fraught start to a year that is supposed to celebrate her seven decades on the throne. And yet for all the questions surrounding the Prince’s Foundation — which have already led to the resignation of its chief executive — the downfall of Prince Andrew is likely to leave a more lasting stain on the House of Windsor.