Nian Yi'an returned from school just as his father, Nian Tingchu, happened to be home.
"Dad?" He expressed slight surprise. "Aren't you on a business trip? How come you're back today? Have you finished your work already?"
Nian Tingchu first took a sealed test tube from the freezer, then explained, "I left in such a hurry this morning that I forgot to take something with me, so I came back."
"It's rare for you to be so forgetful," Nian Yi'an commented, curiosity piqued. "What's got you in such a good mood?"
A smile, seldom seen, played across Nian Tingchu's face. "You might be getting an older sister."
"A sister? Did you and Mom have another child?" Nian Yi'an was taken aback. "Wait, that doesn't make sense. Even if you did have another child, I would still be older. Unless—"
He had an epiphany, his expression turning to one of disdain. "Did you have a child behind Mom's back?"