During the opening of this episode, it is revealed that Milli's favorite game is Hide and Seek, and that she's a really good hider with her dress because of her ability to change her dress to any pattern or design, by means of camouflage.
This is the first episode aired, but not the first episode produced - the first episode produced was in fact "The Big Boat Race."
The series premiere had two (2) episodes premiered on the same day, which were this episode and "The Aquarium Fix-It."
This episode, along with "The Aquarium Fix-It," both premiered on the same day that Episode 4208 of Sesame Street premiered on PBS Kids.
Coincidentally, that Sesame Street episode was also about counting!
This episode aired in 2010, but was made in 2008, since that was the copyright year mentioned in the credits.