Mike Tindall and Zara speak out about 'biggest challenge' in marriage as royals open up

The Tindalls have revealed their secrets to handling marital issues (Image: Karwai Tang/WireImage)

Zara and Mike Tindall admit that having children is the 'biggest challenge' in their marriage, but accepting change helps keep their relationship strong.

The King's niece and the former rugby international first met over 21 years ago, married in 2011, and now share three children - Mia, Lena and Lucas. While they don't undertake official Royal duties, Zara, Princess Anne's daughter, and her husband frequently attend prominent occasions and are recognised for their warm demeanour.

However, during an appearance at the Beauty Awards, Zara revealed that their formula for marital happiness is to "accept that nothing runs smoothly ever."

She told the Daily Mail: "We've been togeth