Queen Elizabeth's eldest grandson, Peter Phillips, is engaged to Harriet Sperling. The two announced that they had taken the next step in their relationship on August 1, 2025. The royal proposed with a three-stone diamond engagement ring that's estimated to cost $42,000.

Peter Phillips and Harriet Sperling are engaged! And according to diamond pro Mike Fried, Princess Anne's son spent some serious bucks on the meaningful ring.