Do you mean the browny-orange on his back? If that's what you're concerned about you don't have anything to worry about. It's just buck grease, all intact boys have it. 'Cause your kids are nakkies you could easily wipe them with a baby wipe.
unlike my boys they are all lazy :lol: and FULL of Buck Grease thats really built up under their fur all flaking out... I wanna get it outta there but you cant get in there :?