I've thought a lot about this, as I am a Person with Parkinson's. I was diagnosed 5 years ago and am tolerating medication well. I do Nordic Walking, non-contact boxing, Irish set dancing, gym classes etc. and so am pretty fit for a 64 year old. HOWEVER, Parkinson's is a degenerative condition and I know I will become less able as the condition progresses. Rather than try to tell my grandson, who is now 4 and a half years old and still enjoys all the things I do, like swimming, fast walking, cycling, visits to the funfair, I wrote some stories about a Granny with Parkinson's. Stories tell the child about someone else, not about you, but they still raise the issue. I've worn my "I have PD. Please give me time" wristband, and my PD T shirt and grandson has seen my PD friends and me Nordic walking, most more afflicted than I am, but so far hasn't asked any questions. I'm sure he will, very soon, and because I'm up-front about it, there won't be any fear or embarrassment surrounding it, I hope. Open the box when they are ready, I say. A bit like sex education. Too much too soon won't mean anything. But silence creates fear and confusion, in my experience. Good luck, you all.