Queen Elizabeth once caught her mother out after she'd been secretly drinking gin.
Ballet dancer Wayne Sleep recalled being at Clarence House when the 91-year-old monarch discovered four empty bottles of the alcohol after they had been drunk by the Queen Mother, who passed away in 2002 aged 101.
Speaking on 'Celebrity Big Brother', he said: "I think some delegate from Ghana was over and invited to Clarence House.
"And the queen came along, just the three of them, and she went, 'What would you like?' She said, 'I'd like a gin and tonic'.
"She said, 'no worries at all'. Opened the cupboards. There were four empty gin bottles there and she turned and went, 'Mummy!'
"That was the queen with the Queen Mother. 'Mummy.' Empties."
In April, Major Colin Burgess, who was the Queen Mother's equerry for two years, revealed she was "far from being an alcoholic" but did love "social drinking", and used to have her first beverage of the day at noon.
He recalled: "What was memorable was her fondness for red wine, particularly heavy clarets, which she loved. We must have got through a bottle- and-a-half at that first meeting.
"Following my appointment, I discovered the Queen Mother's pattern of drinking rarely varied. At noon, she had her first drink of the day - a potent mix of two parts of the fortified wine Dubonnet to one part of gin.
"This was followed by red wine with lunch and, very occasionally, a glass of port to end it. Later came the ritual observed at 6pm, deemed the earliest acceptable time for an evening drink.
"'Colin, are we at the magic hour?' the Queen Mother would invariably ask, and I'd mix her a Martini. After a couple of these, she would sit down to dinner and drink one or two glasses of pink champagne."