Matt Parkman Jr. was first seen at the end of Shades of Gray when Hiro and Ando followed Rebel's instruction to "Save Matt Parkman." Hiro and Ando mistakenly believed Matt Parkman had somehow been turned into a baby. After the babysitter left, they realized the baby was Matt Parkman's son. His ability to activate things was first discovered in Cold Snap. Matt Parkman Jr. has the ability to both activate and deactivate objects, which caused Hiro to title him "Baby Touch and Go." When he activates an object, it follows its natural operational inclinations: if he touches a TV, it will run even if unplugged, if he touches a movable toy, it will animate itself. His powers are not limited solely to technology, however; he was able to reactivate Hiro Nakamura's ability to stop time that had been sealed by Arthur Petrelli during Volume 3. While activating an object requires a direct touch, Matt Parkman, Jr. can also deactivate anything that he is in proximity to but not directly touching, typically when he's upset. He deactivated Hiro and Ando's rental car and a commercial truck, but only while he was not kept amused.
While Matt Jr's reactivation of Hiro's power was a blessing at first, there is a cost: Hiro's body began to reject his ability to freeze time, causing nose bleeds, blood to drip from his ear, and even caused him to pass out. It is uncertain if this is because he was no longer in Matt Jr's direct proximity or if it simply took time for his body to hit a critical point that caused the blood vessels in Hiro's head to rupture. It is also unknown if Matt Jr will be able to reactivate Hiro's full powers when he is old enough to consciously direct the activation.