Billy a rescue stray has made a complete difference to an autistic child, Fraser Booth, and brought him out of his shell.

Before Billy, Fraser was born screaming and became overwhelmed by everyday activities. Every day life can be a challenge for Fraser. (Daily Mail)

When Fraser was a two-year-old, he met Billy at the cat protection shelter. Billy purred and laid his paws across Fraser, and they have been inseparable ever since. Slowly but surely Billy has transformed Fraser's life.

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Billy is always there to offer a reassuring paw.

"If Fraser is around or playing in the garden, Billy is never far away. It is like he is watching Fraser and calming his behaviour," Fraser's mom, Louise.

"He always appears when Fraser is getting upset and offers his head close to Fraser's to reassure him and recently, when Fraser was poorly, Billy sat on his lap all day.

They say animals can sense things, but Billy seems to know before anybody else if Fraser is going to get upset."

"The first time we took Fraser to see Billy, the cat went straight to him... Fraser sat down on the floor and Billy laid across him with his paws on his legs and just started purring. Fraser said 'This is our cat, he can come live with us,' and that was that."

Billy has taken away the stress away from Fraser and added a lot of happiness and calmness into Fraser's life.

Watch video: Billy the rescue stray brought Fraser out of his shell with the power of love.