Natalie is currently 5 1/2 yr. My measuring ability is sorely lacking but here is what I came up with:
Chest circumference: 21”
under-arm to waist: 6”
waist to bottom of tutu: 7 or 9” (will work this til I run out of Sashay)
Chest @ underarm to shoulder for straps: 4”

12/27/15: chained 90+2. Worked according to pattern but used #F hook for 2 rows at waist just to give a little shaping. Did 8 rounds of mesh including 2 increase rows, 1 as instructed & the otherat round #5.
12/29/15: My measuring was apparently wayyy off because when it was tried on, with the ruffle part at her butt/hip level, the top was just above her waist, the ruffle section was somewhat snug & I think I was supposed to close the round and start the mesh section working from the foundation/cast on rather than the shell stitch edge.
12/30/15: I worked 10 rows from the foundation row to add to the height/length and tugged as much as I dared about the ruffle/mesh area to stretch it out a little more. Natalie picked out some ribbon that I had “in stock” (white with silver snowflakes) for the back lace-up section. I used the H hook & doubled the white yarn to make the shoulder straps. By time I got to the straps she was asleep and I no longer trusted any of my measuring ability so I used the doubled yarn and chained 50 stitches very tightly at all 4 spots (left and right, front and back) and made bows at the top of the shoulders so straps can be adjusted or crossed at the back so they don’t slip down.
It came out well though you can definitely see where I picked up to add the extra rows & if I made it again I might use some pretty elastic for the shoulder straps. I would also make the mesh wider so the ruffled section is looser. Overall I like the concept of the pattern and the instructions were pretty good, especially considering I never used the Sashay style yarn before. The video was helpful though the Sashay yarn was crocheted into a different fabric that was not open like the mesh in the pattern but it was still easy to do & I crochet left-handed!!