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Celebrity stylist and designer Rachel Zoe and husband Rodger Berman welcomed their second son on Sunday, December 22nd. Kaius Jagger joins older brother Skyler Morrison, 2 ½ years old.

WHAT IT MEANS: To rejoice

WHERE IT ORIGINATED:  This is a modern English spelling of the classic Latin Caius, a form of the ancient Roman name Gaius.

POTENTIAL NICKNAMES: The couple is planning to call him Kai – which might get a little confusing since their older son is Sky!

KNOW THIS: The root form of Kaius — Gaius — was commonly used among the Romans, with examples such as Gaius Julius Caesar and Gaius Caligula.

POP CULTURE CONNECTION: Donald Trump Jr. picked the name for his daughter Kai Madison in 2007, while actress Jennifer Connelly has a son with the name.

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