According to KidSmart, kids tend to be heavy sleepers and won't always wake up to the sound of a smoke detector. If they do wake up, they may be scared and hide instead of leaving the house. KidSmart offers an alternative smoke detector. Instead of beeping, it plays a message that you, the parent, record (i.e. James, this is mom, there's a fire, you need to... etc.). It seems like a neat and practical idea as the sound of mom or dad's voice would certainly be reassuring to them if they woke up to a house fire.