[Cha Cha]

While I strongly feel your dogs should all be neutered/spayed, I seriously doubt it will change any dynamics already going on. You have a large dog who will not put up with his possessions being taken away. He's trying to tell the small dog to back off by these warning growls, but the small dog thinks he's mighty enough to challenge. At some point, those warning growls, will become I told you so!