How to guard against hackers?

MaxAP45

New member
Dec 26, 2017
17
0
0
Montana
My brother loves hacking into the accounts of just about anyone, me included. He gets into my site and then reads through the order list -- so I end up being unable to know if there's a new message because he already read it ahead. He's not really bad or anything. He does it for fun though but still, a little privacy would be very much appreciated. Any tips?