We have no idea what Wills was showing off on his mobile but Harry and Charles seemed to find it amusing judging by these photos!
The royal trio were at the first day of the Invictus Games at Lee Valley Athletics Centre in London when William whipped out his iPhone to show off something on the screen.
Charles looked rather bemused at first before breaking into fits of giggles as his sons laughed along with him.
We SO wish we knew what was on the phone!
William and Harry were both sporting official Invictus Games clothing while Charles was as smart as always in his suit. At one point Wills did give his dad an Invictus Games jumper to drape over his knees.
It's no surprise the royals were out in force supporting the Invictus Games as Harry has been the driving force behind them. They unite injured servicemen from across the world in a series of sports events.
The opening ceremony was held last night and attended by William, Harry, Charles and Camilla, Duchess of Cornwall. Unfortunately, the Duchess of Cambridge, Kate Middleton, was unable to attend.
It was announced this week that William and Kate are expecting their second child together but Kate is once again experiencing hyperemesis gravidarum, an extreme form of sickness. She suffered from the illness while pregnant with first child Prince George, now one.
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