Spike was acting weird lately, making weird little sounds and having trouble controlling his fire breath, had some weird behavior changes that no Pony understood because they were ponies

One day you decided to ask him so you waited for him to go to a more solitary and private place so you could approach him and enter slowly in the room

You found Spike sitting on the floor leaning against a wall desperately scratching his very itchy body, some of his scales had fallen off a little, Some of his scales had turned a darker color of purple and others were a dark red, It was the great stage of a dragon the 'moulting', but obviously Spike doesn't know about this