such a cute block. Very enjoyable to watch.

Misty fuse--and until you really press it with steam you can even reposition on the 2nd fabric.

Most definitely Mistyfuse! You can't even tell there's a fusible on your piece. And with this tutorial
http://suebleiweiss.com/blog/mistyfu...ard-technique/
You don't even have to reverse your shapes! Mistyfuse is my go-to fusible. While I like SAS, Mistyfuse has a much softer hand in my quilts.....

I think all the fusible products are stiff and don't really like to use them. So I turn my pieces under, sometimes with the seam allowance over freezer paper shapes, iron/starch well, and machine applique that way.

That was a great video! Thank you for posting it!

Misty Fuse has no paper backing, but I iron parchment paper to it and use that as a peel away backing!

I know that this does not answer your question, but please give this some thought.

Since it is for a baby and will be washed many, many times please consider using something like the Eleanor Burns method of appliqué. I use the same fabric, right side to right side and sew around it. Then slit it in the back and turn right side out. Now you have an enclosed appliqué piece that you can sew down and it won't unravel. You can also put a piece of batting on it before you sew it to make it puff a little, and then cut off the batting outside the seam line.

Just a thought over coffee.....

I like Steam a Seam Lite best, but have used Heat & Bond too with no problem.

And this is a great Edyta Sitar video on choosing fusible web for applique. She should know - she does a LOT of applique!
http://youtu.be/35NgfVRtGKo

I use Wonder Under a lot, but have learned on larger pieces to cut the center out, leaving 1/2" to 1" around the outside of the applique, this way you won't have the stiffness if you applique it with the entire piece, and then I use the center cut outs on smaller pieces.