Charlie Sheen

The 'Anger Management' actor was moved by the plight of Teagan Marti, 15, who suffered  brain, spine, pelvis and internal injuries in July 2010 when she plummeted 100 feet from a Wisconsin amusement park ride  and chipped in to pay for the dog who will  turn on lights, pick up objects and be her constant companion.

After a friend of the family contacted Charlie through his godfather, Charlie said: “I like to pay it forward. People come into your orbit for a reason. You don't always know what that is ahead of time, but if I ignore these requests then I don't have any opportunity to see where these things lead us, or lead me."

However, he does want some input on the Golden Retriever's name, and joked: "I think they should name the dog Charlie."

Teagan's mother Julie – who said the family has encountered frequent financial woes in the years since the accident after insurance for the teenager's therapy  ran out - praised the actor for his generosity and revealed she broke down in tears when she heard about the donation.

She said: "I'm in such disbelief. I was crying. ... What a guy. What a guy."