Prince William and Princess Catherine have reached a major milestone in their romance - 15 years of marriage! Wednesday marks the couple's 15th wedding anniversary. To celebrate, the couple shared a sweet family photo. Check it out: View this post on Instagram A post shared by The Prince and Princess of Wales (@princeandprincessofwales) Awww!!! What an adorable family! While they've reached such a happy point in their marriage and family life, things haven't always been this great.