The yawning is what I'd pay attention to (assuming mucous isn't visible anywhere). But a couple times in a day? Or week? That's an ambiguous statement, as bp's don't yawn all that often. I have an adult pewter female that has a whistling sound every now and again since I've had her. She's perfectly healthy; she eats and breeds just fine. Check for mucous in it's mouth or nostrils. Pay close attention as this bacterial infection can be easily cured, but will otherwise cost your snakes life.
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