Add spaces: Itisincrediblehowtheycapturetheattentionofeveryoneintheroomfromtheoldestpersonwhois75(hesnuckin,ashe'syoungatheart)downtotheyoungestteenagers.
It is incredible how they capture the attention of everyone in the room from the oldest person who is 75 (he snuck in, as he's young at heart) down to the youngest teenagers.