"Unlikely," William answered without having to think about it. "We weren't in the same area of the castle, we weren't casting the same spell -" (or any spell) "- and we weren't reacting to a threat." Not that he knew of, anyway. "If it's happened to us, it's probably happened to more people."
He carried his newfound friend back over to where Pete's lion looked like it was currently in feline heaven, eyes closed and rumbling under Pete's hand. He'd intended to - cautiously - reach out and touch, find out if Pete's Patronus animal felt the same as his, but something buzzed under his skin as soon as he began to extend a hand, a feeling of wrongness and violation that left him slightly shaken.
"They're not just animals, either," he said, retracting his hand and wrapping it comfortingly around his worriedly twitching mongoose. "Patronus means 'protector.' I think possibly they're doing that, in some way." He meant to ask Pete if he could touch William's mongoose, but just the thought made bile rise in his throat, made him feel almost physically ill. His mongoose tucked a furry head under his chin and pressed close, reassuring.