PHOTO: CHEFFINS

– Prince Harry was “constantly in trouble at school”, candid letters written by Princess Diana reveal.

The notes, sent to ex-Buckingham Palace steward Cyril Dickman, also describe how a young Prince William “swamped” his new baby brother with “an endless supply of hugs and kisses”.

The handwritten correspondence is to be sold at auction later.

Photos, Christmas cards and cake from the Queen’s wedding will also go under the hammer.

The letters form part of about 40 lots from Mr Dickman’s former estate, which is due to be sold.

The lots are each expected to fetch £80-£900.

Cheffins, a Cambridgeshire auction house, said the letters formed part of “a unique collection of Royal memorabilia”.