Meghan Markle and Prince Harry’s son Archie became a brother last Friday with the arrival of his little sister and the couple’s second child Lilibet “Lili” Diana. People got detail from a source on how the Duke and Duchess of Sussex prepared their newly-two-year-old son for Lili—and the end of his only child days.

The source noted that Archie is a little young to recognize what it means to be a big brother at this point. But Meghan and Harry made an effort to get Archie ready as best they could: “They prepared Archie by talking a lot about the baby,” the source said. “He is too little to understand though. He is big enough though that he is now starting to have his own life too. He enjoys preschool and outdoor activities. He will have a fun summer. Meghan and Harry are also taking time off to focus on their family.”

A spokesperson for Meghan and Harry told People that Archie “is very happy to have a little sister.”

Meghan and Harry opened up about their first impressions of Lili in a statement released announcing Lili’s birth on Sunday. “On June 4th, we were blessed with the arrival of our daughter, Lili,” they said. “She is more than we could have ever imagined, and we remain grateful for the love and prayers we’ve felt from across the globe. Thank you for your continued kindness and support during this very special time for our family.”

This story originally appeared on ELLE US

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