We had seen many examples of the Mane Six being responsible and dependable before this point.  Though if there is one member of the Mane Six who has a problem putting aside her need for fun when it comes to caring for others that would definitely be Pinkie.  So, putting her in a situation where she's being responsible for young children actually does seem like it would be a good challenge for her character.  But how well does the actual story hold up?  Let's take a look.

Headcannons Video:
https://www.youtube.com/watch?v=JFmdoqGLq3c

DRWolf Narrator by DavionX:
http://davionx.deviantart.com/art/DrWolf-Narrator-377863090

All other Characters and Images belong to Hasbro.