Would be grateful if you could share your experiences of this with regards to ASD.
With my DS (6) he has a thing about DVDs. Not the actual film but the trailers and the extas on them. He remembers exactly which things are on each DVD.
But this obsession seemed to make him frustrated and anxious - he took them in and out of the boxes and they got so scratched up they didn't work anymore. So we removed them from the house.
Anybody else have this? I'm happy to foster any obsession he has really, but this one felt like a punishment!