It was a kids movie or tv show. I watched when I was very young, around early 80s. It was in English although I can’t remember anybody speaking. I was either in Germany or Kansas at the time. It may have been Australian but don’t know. The story centered around a young child( a girl I think) who was very sick and quarantined.  The only thing that keeps this girls spirits up is a stuffed kangaroo that comes to life and takes her on adventures in her mind.  End of the movie she recovers from the sickness and is let out of quarantine, but all her possessions have to be destroyed, including the stuffed kangaroo. Which is a sad scene but you see the kangaroo come to life and runs off through the forest to help another kid. This might have been a mix of animation and live action.