Swatch it and see what your stitches per inch are, that should give you an idea. Honestly, though, fit isn't a HUGE issue with this since it isn't shaped. If it's a little big on her, it will fit longer.
Just measure to figure out how long to make the straps- I had to shorten the straps on the one I made for my 5yo because it fell a little too low on her.
Mommy to two wonderful girls
"I don't have to conform to the vagaries of time and space, I'm a loony!" -Campbell Bain (David Tennant) 'Takin' Over the Asylum'
OTN: Cabled Sweater
, arm warmers, kids' clothes