The Princess of Wales wore a bright red bow-trimmed dress, pillbox hat and some meaningful jewelry for the annual celebration.

The Princess of Wales paid homage to both women through her thoughtful jewelry choices on March 10. Kate Middleton often pays homage sartorially to her late mother-in-law Princess Diana, including at today’s Commonwealth Day service.

The Princess of Wales was all smiles inside and outside of the Abbey with Prince William on Monday. The service was also attended by Princess Anne, and the Duke and Duchess of Gloucester. This year’s Commonwealth Day theme was "Together We Thrive.