While we're sharing dragon horror stories, one of my childhood friends had Pearl and Fiery (I was so jealous >.>). But her Fiery got mangled by a lawnmower.
Fortunately it was close enough to the time of release that her folks wrote to Hasbro and she got a replacement.
I wanted Pearl and Fiery so much as a kid that the memory stuck with me.
I had Sapphire and Smokey and I loved them a lot...
But you know, Pearl and Fiery are the best.
I've had doubles of all the dragons over the years, they used to be semi common at the carboot sale. But Fiery and Flash are the ones I generally had more trouble locating. I got mine I think in a big tub of accessories from another local collector (great tub that, £10 for all the dragons, princess accessories, most big brother accessories and a ton of ponywear). But I don't remember getting doubles of either of those two.
I would imagine they'd be the harder ones to nail down.