I made these cupcakes also for Aubrey's third birthday when we went to the park with cousins.
For the tinkerbell dress I used green frosting in a piping bag with a small rose tip. Starting at the edge of the cupcake I slowly piped with an up and down motion to create the ruffle. I overlapped the next layer and did the same thing around until I got to the center.
The top of the dress I made with green fondant and a small heart shaped cookie cutter. If you don't have a heart shaped cookie cutter you can also use a five petal flower cutter and cut off the other petals to create a heart.
The wings I made out of white melting chocolate. I drew a template of what I wanted the wings to look like then transferred the picture 8 times on the backside of parchment paper. Then using the melting chocolate I traced the template. These are very fragile so I made plenty of extra just in case, thankfully I only broke one wing.
For the rose cupcakes I used a rose tip and piped out the rose petals to the edge of the cupcake.