"Jaime," he dropped the gun quickly, so quickly he nearly lost his grip on it and had to stumble to get it properly secured in his grasp again, at which point he promptly put both his hands behind his back, as though attempting to hide the gun. He didn't really think through why he did any of these things. River was probably still laughing at him. "I didn't... I was..." worried that you were killer pollen didn't sound like a reasonable end to that sentence. "Haven'... seen y'around, much," he decided on finally.
At her mention of River, he looked around as though expecting to see the girl. He then sighed, and ran the fingers of the hand not holding the gun behind his back through his hair and said, "Sorry 'bout... she's a mite... curious, at times. Don' righ'ly know when too much is too much. She's... harmless, though," For the most part. At the very least, he figured that Jaime didn't have anything to worry about. He doubted she knew any complex government triggers, and for all he knew River was immune to those sorts of things now. He thought the Doc had mentioned... "Glad she's not pest'ring you, though," he said with a slight nod of his head.
He was starting to calm slightly, his arms going lax and the gun coming back into sight. He was starting to forget about the plants too. Sort of. For the most part anyway.