Why do Smoke Alarms Go Off In The Middle Of The Night?!!

 Last night at 3am we heard a "chirp...chirp... chirp..."  UGH!!!  Seriously - why do smoke alarms always go off in the middle of the night?!  This happened to Jeremy and I prior to having kids, but the entire system went berserk - SO LOUD.  Jeremy shot out of bed and ran down the hallway screaming at a very high pitch.  I thought we should throw the stereo through the window to get out.  Thankfully didn't act on it.  

Grateful that it was only two of them that were chirping.  Unfortunately one was in Riley's room so she was awake and Jeremy had to go in and fix it.  Then somehow fixed the others upstairs before coming down to get to the one in the kitchen area.

And it wouldn't open!  Nothing we tried would open the battery compartment.  Thankfully I found a YouTube video that showed that there is a lock pin that can keep the compartment from opening.  Jeremy disconnected the alarm from the ceiling.  He ripped off the small section of paper on the top and used a flathead screwdriver to get the lockpin out.  And voila - it opened.

We were up for a while.  Got very little sleep.  I love/hate smoke alarms.