Dad Andrew Keher had put his one-year-old daughters to bed, but made a blunder by leaving the light on.
An hour-and-a-half later, he heard little Megan and Molly giggling, so crept up to their room to find that the sisters were far from snoozing – and instead playing a game!
Photographer Andy filmed his girls as they ducked behind their cot's bars, before jumping up and making each other chuckle with delight.
Speaking about the sweet sight, Andy, 31, was quoted in the Daily Mail explaining: "I just forgot to turn the light off so they obviously thought it was still playtime. It could have gone on for hours if I hadn't interrupted them."
The Merseyside father uploaded the adorable clip to Facebook and just hours later, the video had gone viral. It has now had a whopping 2.6 million people tuning in worldwide.
Mum Lucy, 32, said: "I was shocked. We never expected millions of people to be interested."
Andy added: "They're little stars in the making. I can't wait to embarrass them when they get older."
Check out the heart-melting video below:
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