The 32-year-old granddaughter of the Queen was spotted bottle feeding her new arrival, dressed down in jeans and a navy gillet, at Brampton Bryan in Hertfordshire.
This isn't the first time Mia's spent a day at the races. Earlier this month Zara was seen carrying her new arrival over her shoulder as she headed out to the Gatcombe Horse Trials.
Last month, in a somewhat controv move for a royal couple, Zara and husband Mike Tindall sold the first pictures of Mia to Hello! magazine.
Zara and Mike Tindall introduce gorgeous baby Mia in this week's issue of HELLO! magazine. Pick up your issue now! pic.twitter.com/i9heaS7Tdi
- HELLO! (@hellomag) February 24, 2014
The mag cover came as quite a surprise as Zara and Mike kept the birth of Mia pretty low key and din't even pose for the traditional photos outside the hospital after the birth.
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