(AP) -- Santa Anita is celebrating the birth of Zenyatta's colt with an equine baby shower on Saturday.

The track will give away "It's a Boy" posters free with all paid admissions and Team Zenyatta will have an autograph session before the races begin.

The superstar mare, who won 19 of 20 career races before retiring in November 2010, gave birth to a colt for the first time last Thursday in Kentucky, where she lives at Lane's End Farm.

According to a post on Zenyatta's website, the colt does not yet have a name. Per standard practice in the breeding industry, he is referred to as "12 Zenyatta," which indicates the year he was born and his mare's name.

Members of Team Zenyatta, including owners Jerry and Ann Moss, trainer John Shirreffs, Hall of Fame jockey Mike Smith, and Dottie Ingordo Shirreffs, the trainer's wife and racing manager for the Mosses', will sign autographs on Saturday.

Several charities that have been involved with Zenyatta during her career will be represented at the event.

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