Wales, UK - When Simba was about to enter a new home for the second time in his life, the little dog faced a seemingly insurmountable obstacle: the front door.

After his previous owner was no longer able to look after his pet, Simba was handed over to Many Tears Animal Rescue in Wales.

Simba, who was already nervous by nature, became even more unsure of people and his surroundings, and he was slow to gain confidence.

When a new couple adopted him, he was reluctant to cross the threshold of his new home, and his journey was captured on TikTok.

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In the footage, Simba can be seen initially refusing to enter his new home, preferring instead to stay outside and linger near the door.

"One day everything changed," says the clip, which quickly went viral.

The video shows Simba finally daring to enter the house. He jumps onto his owners' bed, romps around, relaxes on the sofa, and lies down comfortably under a blanket.

"Simba has continued to smash it at life in his forever home! You’ll be happy to know he’s FULLY an indoor dog now and is now super confident in his forever home," the dog parents wrote in their video caption.

"Time is the best healer. At the start we never thought Simba would voluntarily come near us or even come inside the house/enjoy his walks but he’s finally there!" Simba's owners wrote in the comments section. "Lots of tears were shed at the start but it’s the most rewarding thing you’ll ever do as a dog lover."

Their idea was to give Simba as much time and space as possible so that the little four-legged friend could develop a feeling of safety and security. And it worked!

"We still can’t get over how much our once nervous boy has improved over the past months, he’s a completely different dog with such a cheeky + funny personality," they wrote in the caption of another video.

"We can’t wait to see what the future holds for our boy."