Rachel Zoe’s son Kaius, having his hair cut by celebrity hairstylist Joey Maalouf. Photo: Instagram.

Celebrity stylist and fashion designer Rachel Zoe gave her three-year-old son his first haircut on Wednesday, as per Jewish tradition.

Zoe, who is Jewish, shared on Instagram a photo of her son, Kaius Jagger, getting his locks snipped by hairstylist Joey Maalouf. She captioned the shot, “Big night tonight…huge,” followed by the hashtag, “#thisis3.” She later shared another picture of Kaius, with his new hairdo.

The Jewish “upsherin” custom requires a boy’s hair not to be cut until he is age three. The website of Jewish outreach group Chabad explains that a child’s third birthday “signals a major transition in his or her education.”

Zoe is also the mother of 6-year-old Skyler Morrison. She has been married to Roger Berman since 1995.