Kate Waterhouse shows off baby bump in a bikini on Instagram.

Sydney racing royalty, columnist and blogger, Kate Waterhouse has shared a rare photo of her growing baby bump.

The 30-year-old, who is 27 weeks into her pregnancy, uploaded a gorgeous photo of herself in a Zimmermann bikini on Instagram.

Waterhouse married former NRL star Luke Ricketson, 41, in June 2012.

Kate and Luke’s baby is due in June, and it will be the second grandchild for Robbie and Gai Waterhouse. Kate’s brother, Tom and his wife Hoda welcomed a daughter named Rose in 2013.

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