A 14-month-old girl fell asleep while riding a toy train in circles in her living room after being momentarily left to her own devices.
"Vivienne was having a blast on her older brother's train. She knows how to mount and dismount, etc., so I wasn't worried when I went into the other room to respond to a work email," the video's uploader wrote.
"She became oddly quiet (you know, like when they're being mischievous), so I quickly headed back to check on her. She had fallen fast asleep! Melted my heart :)"
We totally get why -- playtime can be hard work!
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