Phillips is due to give birth early next year.
A statement from Buckingham Palace confirmed the news:
“Mr and Mrs Mike Tindall are very pleased to announce that Zara Tindall is expecting a baby in the new year.
“The Princess Royal and Captain Mark Phillips, Mr Phillip and Mrs Linda Tindall, and members of both families are delighted with the news.
“This baby will be the first child for Mike and Zara and the third grandchild for the Princess Royal.”
When Princess Kate and Prince William welcome their son or daughter in mid-July, Zara will be 15th in line to the throne.
Phillips and Tindall married in July 2011 in Scotland.
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