Conection lost - timed out

My grandson and I bought Mine craft 06/28/2014. We sit side by side and have been playing multiplayer since day one (06/28). About a week ago we started getting dropped from multiplayer with message:
Connection Lost Timed Out

We have tried getting rid of some worlds ; We have tried logging into each others world - joining the other person - in every case we can play about 1 - 2 minutes then the one joining gets dropped with message Connection Lost Timed Out