My buddy's router keeps a log of recent activity, you can watch what's going on in there.. gives full url's and everything. Mine doesn't do this though.
Hey all I want to know what sites people in my family are visiting so is there a way to log it
Make more sense to ask them.
Otherwise, if you are a parent and those are your kids, use parental control on their computer instead of "Dirty" spying.
He's not the parent, he's the child.