A UK mum jumped into a river to save her son's favourite stuffed animal.

Lou was busy carrying her two-year-old son Tommy home from a family dinner when an unexpected gust of wind swept across them.

The UK mum watched in horror as the strong breeze snatched the toddler’s favourite soft toy from his hands and carried it away.

Unfortunately, the mother and son were crossing a bridge over a river at the time – so 'Bun Buns the Bunny' ended up flying straight into the water.

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The stuffed rabbit had been Tommy’s favourite toy since he was born… and he had never spent a night without it.

That was at the forefront of Lou’s mind as she watched the toy begin flowing down the fast-moving river…

“I said to my partner, ‘I’ve got to get him,’ and he said, ‘You can’t go in there, it’s disgusting!’” Lou revealed.

“My little boy has never slept without that bunny. He has had it since birth. I have tried to find him a replacement but he just doesn’t take to anything else.

“I just thought, ‘I need a good night’s sleep tonight’. I had no choice but to go in and get it. I could see it bobbing up and down on the water.”

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So Lou decided to jump off the bridge into the water like an absolute legend to save her son’s precious toy.

“I gave my engagement ring to a stranger, got a hair bobble from another woman to tie up my hair and cannonballed off the six-foot (1.8 metre) high bridge,” she described.

“The current was strong so I was trying to tread water. It felt like there was a load of eels at my feet and I was covered in sludge. The rabbit had gone about 60 metres downstream.

"Once I had it I swam back to the bridge. When I was there my partner had to pull me out because I was starting to sink into the sludge. Luckily, my car was only about a minute’s walk away."

A passerby witnessed the dramatic rescue and was shocked that Lou had jumped into the fast-moving river to get the rabbit.

“I happened to look in the river to see a cuddly toy in there and thought, ‘That's a shame’,” Cameron Love described.

“I then noticed someone trying to help somebody out of the water and realised it was the woman’s partner.”