Congrats on the Pershing. One of my personal favorites. The Pershing does have the reverse safety feature as has been mentioned. You must put the throttle in the full reverse position then forward to "unlock" the drive function.
Also you may want to inform your brother of the gentleman's 3 foot rule. Never get any closer than 3 feet to another tank. many highly detailed tanks have been damaged from someone new to the hobby not knowing of the rule or understanding how much damage can occur from being a little careless or reckless even.