Princess Charlotte I'm Gettin' the Whole Royal Thing Down!!!

6/12/2016 8:35 AM PDT

Princess Charlotte is only 1, but she already knows how to wave to her subjects.

Kate Middleton held her youngest Saturday at Buckingham Palace ... for the Trooping of the Colour.  It's all part of the celebration of Queen Elizabeth's 90th birthday.

Kate and William definitely make cute kids.