A few months ago I saw a girl on the playground wearing a shirt similar to this one. I thought the idea of the ruffly sides was really cute. Unfortunately, since I did not know the child I could not just walk up to her and take a closer look, or even take a picture, so I made this from my memory. I actually really don't remember what the shirt looked like, but I think this one turned out kind of cute :)
Anyway, it is really easy to make, you just need to alter a normal shirt pattern a bit. I will briefly talk you through it, but I don't have to explain much, if you know how to make a regular t-shirt...