THEY say a dog is man's best friend, and in the case of Duncan Evans it's clearly true.

Duncan has constructed a custom-built motorised stairlift to help his beloved pooch take the weight off.

Sixteen-year-old Jack Russell Timmie struggles with arthritis in his legs, and after a nasty fall down the stairs Duncan decided his four-legged friend needed a bit of extra help.

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"The stairs were too steep for his little legs," said Duncan, from Login, near Whitland, in west Wales.

"Timmie has to take lots of medication for his enlarged heart and problems with his lungs, so he's not emant to do strenuous exercise.

"And it wasn't just a case of getting down the stairs, he has to get up them too.

"He's quite old, and although he can get up and down ok now, but I wanted to preserve his life and that little ticker of his."

Inspired by a similar device he spotted online, Duncan set about making his own version that would work for Timmie and his owners.

"I asked myself, do I play it safe and make it really simple (boring) or do I go all out and make it the best thing I can?" he said.

"It took him a bit of training but he can manage it all by himself now, what a hero!"

And this isn't the first time Duncan has got his tools out brighten Timmie's day.

Earlier this year, he set to building the pooch his own cardboard 'hotel' in the style of the Home Alone house (thankfully without the movie's signature boobie traps).

Western Telegraph: Timmie in his 'dog hotel'

Timmie can also accompany his loyal owner on skateboard adventures, in this creation.

Western Telegraph: Timmie in his motorised skateboard buggie.

Duncan, who has shared his videos under his YouTube name of Curlykidlife, has already earned more than 2,500 views for his latest creation.

And his doggy hotel video has been watched more than 46,000 times!

To see more of Timmie's adventures, search Curlykidlife on YouTube.