Christian the Lion was born at a London Zoo, which sold him to a pet shop where two young Australians bought him in 1969. They raised him as a pet for a few months, and he grew from 35 pounds to 185 pounds.
The local authorities said they could not keep him, so they sent him to George Adamsonís animal sanctuary in Kenya where he lived free and around humans who fed him. A year later the Aussies went to Kenya to visit their friend Christian the Lion and had a heartfelt reunion. The story was made into a movie.
There are lots of short videos about this reunion. I like this one, with scenes taken from the movie, and with the lovely and very appropriate background music of Whitney Houston singing I Will Always Love You.
Related: Extraordinary Gorilla Reunion