There's a moment of hesitation from Vash. A nervousness of allowing his brother to roam anywhere near this town without supervision.

"Maybe I'll drop the boys off with Cyril for lunch and join you? Give him some one of one time with them." He tries to sound casual about the suggestion. Seeing how his brother might react to the idea of leaving the kids alone with Cyril and the idea of having Vash as a constant shadow.