Kendall shoplifts for the first time at age 12. It's ridiculous, he could afford to buy the whole store with his allowance alone, but something about casually lifting a packet of painkillers off a shelf and dropping it in his pocket on the way out gives him a buzz. The child psychologist he sees for his stutter would probably say he's doing it for attention, acting out so his parents will take notice. The flaw in that theory is that he never gets caught. He's really good at shoplifting.
He amasses quite a collection of stolen goods, which he keeps under his bed. The people who come in to clean must wonder about the pile of seemingly random stuff hidden there, but no one ever asks him about it. He eventually gets bored and stops.
The first time he steals again as an adult, it is a kind of cry for help, a please arrest me, punish me. Put me on the front page of a rival newspaper, Troubled Son of Media Mogul Caught In the Act. It doesn't work. He's still too good at it.
He throws out the stolen batteries as soon as he leaves the store. He goes back to steal some more a few days later.