Two Note 4's bought at the same time both died within 3 days of each other!?! Coincidence?!?

[AC Question]

So yea I bought my wife and son both Note 4's about a year ago and they both go out within 3 days of each other. I have another Note 4 that works so I robbed the battery from it and nothing. The batteries from the two bad phones will work in the good Note 4. (The good one came from Verizon and the bad ones from ATT)
I have tried every button hat trick out there and nothing works, they have no sign of life plugged in or not. The ONLY thing that gets any response is if I plug into my computer the computer will make notification sound that USB was plugged in. This all happened just days after an update came through about two or three weeks ago.
Any ideas or am I just screwed? I don't feel like this is just a coincidence. Several other phones and tons of electronics so I know it wasn't an EMP =/

 

[nahoku]

Since you state you've tried every hat trick, I don't know what to recommend. I'm guessing you tried pressing and holding the power button for longer than average time to see if the phone turns on? How about pulling the battery, and depressing the power button multiple times (over a second or two) to try to get rid of any stray charge, then reinsert the battery and try to power on again.

I also have to ask if you've tried booting into recovery or download mode? Its tough on a forum to decipher what all people have tried when they say they've tried everything.