When Will Stoltenberg first saw the Staffordshire terrier/Chihuahua mix at Massachusetts Society for the Prevention of Cruelty Animals (MSPCA) Angell Animal Medical Center in Boston while volunteering, he felt drawn to the dog.

“I couldn’t help going to visit him every time I went to check on the dogs,” Stoltenberg tells PEOPLE. “He showed a truly wonderful personality by pushing up against the kennel door to get scratches every time I passed.”

Even though Clefford had a shy temperament and a cleft palate, Stoltenberg was still surprised to find that the dog had been overlooked by adopters for months.

Special food and a potential surgery didn’t hold Stoltenberg back from falling in love with the canine. He decided to adopt the dog and see Clefford through the treatment he needed to fix his cleft palate.

Clefford is now on the road to recovery and his sunny personality is bursting through the cloud of his difficult past more every day.

After Stoltenberg adopted Clefford, he found that the “nervous but loving” dog was scared of “women, vans, bikes, skateboards, motorcycles and runners.”

“With time and positive training, contact with his fears took on the form of learning experiences,” his owner says.

Stoltenberg has helped Clefford heal physically and emotionally, and the dog has returned this kindness in devoted companionship.

“Adopting Clefford was one of the best decisions of my life. Clefford Is now truly a family member and I can’t imagine a world where I didn’t adopt him,” Stoltenberg adds.

The shelter volunteer hopes his decision to bring Clefford into his life shows others that animal rescues are full of pets waiting to be your best friends.

The Internet seems to be taking notice of this message: a post Stoltenberg put up on Reddit about Clefford’s journey attracted a lot of attention and more than 600 adoring comments.

Now that Clefford’s cleft palate has been addressed, Stoltenberg plans to find new ways to make his pooch pal’s life more comfortable.