He was already aware of what Liz was doing. Since they had arrived nearly one month ago, the elder Thompson had been strategically tilting picture frames, blowing out candles, and turning up rugs. The immensity of what she did escaped her, he knew. Kid was being tested. In one of his ephemeral fits of wisdom (which were ever at odds with his compulsions), he resolved to wait her out, and pass her test.
But as easily as it was resolved, it was infinitely more difficult to carry out. He felt an acute humiliation that he'd never felt before when he finally understood that passing this test meant showing Liz his weakness. Not just showing her, but making her believe it.
And eventually, this came about. He entered the mansion's front door, Liz and Patti behind him, and noticed immediately that the paintings had not only been tilted, but switched around out of order. He visibly winced, and turned his head to see Liz staring at him in curiosity, as if to see how far he was willing to take things. In that one short moment, a new understanding passed between them.
Liz stood still in amazement for a crawling moment, entirely unaware that every fiber of Kid's being, and everything he knew about the world and his place in it, was crying out for him to salvage the mess of disorganization.
When she moved again, it was to help right the mess she'd made. Above all, Liz was wary, but she was not cruel. The person who'd recruited them was genuinely a slave to his compulsions, and even if she didn't understand, she wanted to make things easier. Make things easier, the way he had done for them only one month ago. When they had finished, they stood together, surveying their handiwork. Kid looked at Liz.
"Do you think you can understand?" He asked. "I can't stop it. No matter what I try." A thousand thoughts flitted through Liz's head, but in the end she nodded.
"I gotcha. Don't worry about it so much, not with me around." He smiled a tiny smile, and she returned it before they both went to find Patti.
A/N: the whole situation where people purposefully mess things up to aggravate OCD is close to my heart, and that's where this came from.