OK! Exclusive: Find Out How Kate Middleton Plans To Keep Princess Diana’s Memory Alive For Her Children

“It’s kind of like a dowry or hope chest and has things in there that the boys have kept from when their mother was alive,” a source exclusively told OKMagazine.com.

Although Her Royal Highness has never met Princess Diana, the chest was all her idea! “She’s still her babies’ grandmother and wants them to understand just how special she was to the world,” the insider dished.

Along with jewelry and letters that belonged to the late royal, the chest will also include “photos and even recorded tapes that Diana used to make for the boys when she was away on Royal duties.”

An insider explained that the Duke of Cambridge “never saw his mom as a royal figure – she was just his mom, and she adored him and his brother. He had such a happy childhood, and that was all due to her.”

“Having a baby girl who carried her name will be a beautiful reminder of Diana every time he looks at his daughter,” the source continued.