With two daughters under 4 years old in the house, Mark Zuckerberg had to get creative when it came to helping his wife get some shut-eye.
The Facebook co-founder, 34, revealed on – where else? – Facebook that he recently created something he calls the Sleep Box in order to help wife Priscilla Chan, who is a pediatrician and philanthropist, stay asleep at night.
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“Being a mom is hard, and since we’ve had kids Priscilla has had a hard time sleeping through the night,” Zuckerberg wrote of his invention. “She’ll wake up and check the time on her phone to see if the kids might wake up soon, but then knowing the time stresses her out and she can’t fall back asleep.”
Zuckerberg, who shares two daughters, Maxima “Max,” 3, and August, 1½, with Chan, said the dilemma led him to create a small wooden box that sits atop Priscilla’s nightstand and puts out a dim light between the hours of 6 and 7 a.m.
The father of two noted that the light is “visible enough that if she sees it she’ll know it’s an okay time for one of us to get the kids, but faint enough that the light won’t wake her up if she’s still sleeping.”
The box isn’t a clock, and doesn’t show the time so that if Priscilla wakes up in the middle of the night, she knows she can go back to sleep without fear of sleeping too long.
Zuckerberg said the invention has so far worked better than he expected, and his wife is now able to sleep through the night.
“As an engineer, building a device to help my partner sleep better is one of the best ways I can think of to express my love and gratitude,” he wrote. “A bunch of my friends have told me they’d want something like this, so I’m putting this out there in case another entrepreneur wants to run with this and build sleep boxes for more people!”
Since becoming a father, Zuckerberg has previously opened up how parenting has changed the way he runs his business.
“Having kids does change how you think about the world in a pretty dramatic way,” he said during a college town hall in March 2017, CNBC reported.
At the time, Zuckerberg and Facebook announced the company’s extension of its parental leave policy of four paid months to full-time employees of any gender and to same-sex couples.