The Princess of Wales has given a charming glimpse into life at home with her youngest child, Prince Louis — and it turns out he has a rather quirky little habit.

While hosting an outdoor event with U.S. First Lady Melania Trump at Frogmore House on Thursday, September 18, Kate revealed that seven-year-old Louis has developed a passion for collecting conkers.

“He’s absolutely obsessed,” the princess shared with Chief Scout Dwayne Fields. “We keep finding conkers in cupboards, in his bed — conkers everywhere!”

According to Kate, her son even stuffs them into his toy cars and drives them around, turning his growing collection into part of his playtime.

Kate and Melania’s day with the Scouts