While Mary does eat healthily and exercises regularly, being a hands-on mum to Christian, 13, Isabella, 12, and 8-year-old twins Vincent and Josephine, a dedicated wife to Prince Frederik, and fulfilling her royal duties could be leaving the princess exhausted.
The doctor advised that it was important for Mary to take care of herself and have some time alone to regain her energy, especially with her royal family duties.
But with Queen Margrethe slowly stepping back from her duties, it can only mean Princess Mary will be required to take on even more, as her husband, Crown Prince Frederik, prepares to take over the throne.
The Danish royal has yet to respond to the report.
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