Younger brother and his friend are very affectionate towards each other. Advice?

My 10 year old brother and his best friend hug a lot, hold hands, and even openly make-out on the living room couch sometimes, so I was wondering if this is a normal thing for boys to do early in puberty? Should I separate them when I see them kissing each other, or is it OK to let them do that, just as long as things don't go too far? Thanks in advance.

I think that this is not true and you are sick. So my advise is find some other place to get your kicks.