Kate Middleton is one of the UK's most well-known senior royals and is also a mum to three young children; Prince George, Princess Charlotte and Prince Louis.The Duchess, 39, and husband Prince William, 40, might have the royal fortune at their disposal and live on a multi-million pound Norfolk estate, but this doesn't stop the busy parents from saving a few quid here and there.Those closest to Kate have always claimed she's a fan of a simple life, and has been spotted being her best thrifty