It's given a Call Back in the sequel with Little Brother.
From the sequel
Little Brother stowing away in Tai Lung's pack.
Dalang's reaction to the medicine Su Lin gives him. "I don't think Sonam's spots are supposed to be pink…"
Shifu, trying to test Dalang's reflexes, throws a knife at him. Dalang catches it and throws it right back, where it hits the table right beside Shifu's hand. There's a pause, where Dalang realizes what he just did. "I… am really, really sorry." "Oh, no need to explain. It was a reflex. Much like this one." Then Shifu hits Dalang over the head with a wooden spoon.
After Mei Xing chews Shifu out: "I need to go knit something." "Please do."
Tai Lung starts freaking out about being a father, and then the wind blows so hard that a stalk of bamboo bends down and whacks him on the head.
After Tai Lung has used the Phoenix Tear Technique on Koshchei, apparently leaving nothing but a pile of clothes behind, he and Po go to see what happened. "Well, shall we survey the damage? I highly doubt he would be running around in his skivvies somewhere."
"It's a parable, you idiot, it's not supposed to be literal!" Made funnier when you realize the Chinese character for “seed” (zi), is the same one for “child”.