One thing which is quickly deteriorates thanks to having a child is the condition of your back.
All that bending and lifting , the moonlighting as a human climbing frame, the having to heave all that extra stuff around.
So who can blame one cunning dad for coming up with a clever rouse to get a back massage off his son?
Ken Kawamato posted a video of his young son doing just this, all thanks to his T-shirt and a toy train.

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In the footage, we see Ken, a Google software engineer from Japan lying on the floor while his son runs the toy up and down his dad’s back in a massage motion.
His T-shirt handily sports train track patterns over those spots that need a massage the most.
Clever man!
But does it work? Not just as a rouse, but does it result in a semi-decent massage?
The good news is yes, it does.

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Ken later added: "It feels good!"
Now, you too can get your kids to show you some TLC. A Japanese website is now selling the "massage T-shirt" so knackered dads everywhere can enjoy it for around £17.40.
Which, when you think about it, is actually a small price to pay for a back rub.