Princess Diana was very playful when she was still alive, especially with her two sons, Prince William and Prince Harry. But every now and then, she also showed her fun side to her ex-husband, Prince Charles.

In an unearthed photo, the Princess of Wales is hilariously hiding behind Prince Charles. Even though there was so much space around them, the late royal opted to stand behind the heir to the throne.

Princess Diana also had a mischievous look on her face, which proved that she was enjoying what she was doing. In the snap, the mom of two is wearing a green coat and skirt, which she paired with her gold necklace and earrings.

Prince Charles, on the other hand, is wearing his signature suit and tie. He is standing in front of Princess Diana with a serious look on his face. Even though the future king is aware that Princess Diana was standing right behind him, Prince Charles didn’t smile.

In fact, Prince William and Prince Harry’s dad even kept his left hand inside his pants pocket. The gesture suggests that he’s closed-off and distant from his ex-wife.

During a previous interview to commemorate the late Princess of Wales, Prince William and Prince Harry revealed that their mother was a fun mom. In fact, she would usually come up with ways to embarrass her children.

On one occasion, she surprised Prince William with a birthday cake that is designed with a woman’s breasts. She also invited a handful of models to the palace to celebrate the Duke of Cambridge’s birthday.

During an interview, former royal chef Darren McGrady said that Prince William turned bright red upon seeing his birthday cake.

“I came into work that morning and went down to the refrigerator, opened the door and I was just confronted with the biggest pair of boobs I've ever seen in my life. The Princess had ordered a boobs cake for William's 13th birthday. William just went bright-red,” he said.

Prince Charles and Princess Diana Prince Charles and Princess Diana are pictured attending a centenary service for the Royal College Of Music on Feb. 28, 1982 at Westminster Abbey, London. Photo: Fox Photos/Hulton Archive/Getty Images