Their cat wouldn't let them sleep.

[Catherine]

A beautiful ginger cat called Trident was being very annoying one night. He would not let his people sleep. He wouldn't  quit meowing and scratching their door.
Finally they got up. It turned out their dish washer was malfunctioning and was melting plastic. 

https://paradepets.com/pet-news/protecti...ailed-hero

Trident was a real hero. The fumes from plastic are toxic. If he had let them sleep, they probably would have died.
Always trust your pets when they act strangely. They sense things before we do.