Lo and behold! The episode was:
Arthur #1110The girls loved it, and international sophisticates that they are laughed as everyone said "shay-shay" (thank you in Chinese (xie xie)), a gross mispronunciation to them! They are definitely finding validation for their stories by seeing Chinese ballerinas and familiar characters talking about adoption.
"Big Brother Binky", Parts I&II
In this special two-part episode, Binky's family adopts a baby girl from China. Binky receives the news of getting a baby sister with great excitement, and he delights in helping prepare for her arrival and visiting China. Although at times Binky worries about how his life will change, and more importantly, whether his new sister will even like him! - Binky becomes the proudest big brother in Elwood City.