It would take more than a grumpy resting face to have Wren turning away from the stranger now that he'd been given water for no payment first. It was woefully easy to earn Wren's friendship and just by choosing not to abuse the small boy, Sarge had already laid half the groundwork down. Thirsty though he was, he was still aware that there was a limited water supply and he stopped sucking at the bottle when it was about a third empty, pulling it from his mouth and getting his breath back as he held it, not quite offering it back to his new friend but definitely willing for it to be taken from him; he didn't want the guy to go without.
He licked his lips, cracked and bleeding after so long without water and his mouth feeling much less dusty, and listened intently when he was spoken to. He nodded immediately - "I'm a, I can be good1" he vowed, stumbling over his words - and then got up onto his feet like a newborn horse, pushing up on his arms like a collapsible clothes drier before unsteadily wobbling upright. As much as his unsteadiness was from hunger and exhaustion, his ruined feet were the main cause of the way he limped heavily a step or two closer, the pain of it flashing briefly over his face in the way his eyebrows drew in and the way he bit at his lip, but it went as soon as it had arrived - he had been taught that his pain didn't matter to anyone - and he seemed more anxious about taking the stranger's hand than the fact that he was trying to walk on raw wounds, his own small, delicate fingers reaching out and seeking to curl up against the man's larger hand the way he used to do with... he wasn't going to think about him. He was being a good boy and good boys didn't cry.