Prince Harry has apologised for dressing up as a Nazi for a friend's birthday party at the weekend.
The 20-year-old was pictured wearing a swastika armband and other items associated with Adolf Hitler and the Nazi party in the 1930s and 1940s.
The Nazis killed millions of people in the Second World War. The Queen is taking part in a service to remember those who died on 27 January.
A statement said the prince was sorry for "any offence or embarrassment".
"He realises it was a poor choice of costume," it added.
Harry has been in trouble before.
He admitted smoking cannabis as a teenager and was recently involved in a nightclub scuffle with a photographer.
But he's also done some good things.
He has taken rugby coaching at schools and travelled to Africa to make a documentary about children with Aids.
Harry is set to start training as an Army officer in May, but some people say this latest blunder shows he isn't fit for the job.