Prince William has said his mother would be "immensely proud" of the work a charity she helped to set up does with families who have lost loved ones.
The Duke of Cambridge paid tribute to volunteers and staff for their "enormous, positive difference" Child Bereavement UK made to those who were suffering tragic loss.
The charity was launched in 1994 and Diana, Princess of Wales was a keen supporter. William said his mother had recognised the grief losing a child could cause.
CBUK supports parents who have lost children as well as offering help to a child if they experience bereavement themselves.
Speaking at a dinner in Whitehall held for the 21st anniversary of the charity - of which he is patron - the Prince said the organisation embraced "strangers at the darkest moments in their life".
He added: "My mother was determined to help those in need and she would have been immensely proud - as I am - of all that Child Bereavement UK has achieved these last 21 years.
Singer Gary Barlow and his wife, whose daughter Poppy was born stillborn in 2012, performed at the celebration dinner.
Mr Barlow said: "Dawn and I have always felt our own personal bereavement was too painful and private to talk or comment on publicly.
"Instead I will sing joyous music in support of Child Bereavement UK to say thank you for all the help it has given us and many other families."