Rear brakes

I noticed in the last few days that there is a sound that is coming from the back of the truck. At first I thought maybe a u-joint or broken shock wasn't sure so had a friend stand beside and behind the truck to see if he could hear the noise.
The noise is like a sticking/rubbing then it goes away as soon as I move but then when I stop and move again the noise is there again it don't matter if I am going forward or backwards it is there but goes when I move. It is not holding the truck back or anything just that noise.
My friend who is a bit of a backyard mechanic thinks or is sure it is the back brakes sticking and releasing as soon as you move.
He says not to worry it will not cause any damage as it probably the brakes are dry from dust, dry weather or maybe some moisture.
What do you guys think. Please no insults or nasty replies I just want your knowledge and input.No it is not Friday.

 

He is probably correct, but it’s fairly easy to remove the drum and check it out. My 2 cents.

 

Yes that would be the easiest to do but I can't at my age playing around lifting etc etc. I will wait a couple more days and see if it rains it might go away but if not the I will get my regular mechanic to look it over. I just did not want to bother him something that is not urgent. Thanks