I did, however, finish sewing my nephew's Superman cape for Halloween. I made a matching applique iron-on for his mom to sew on to a blue shirt to finish off the costume, which will hopefully be a breeze for her. My nephew is way smaller than my son, so he couldn't quite model the cape for me, but he did do a great job holding it up!
I used a pattern from The Long Thread and simply shortened it to fit an 8 month old baby. Here's hoping it fits, that is, given that he's over 1800 miles away. Alternations would kind of be a pain in the neck. I used Kona Cotton for the whole thing, and made a Superman applique stencil out of some line art I found on Google Images. All in all, this took less than 2 hours to complete, and a good chunk of it was tracing and cutting the applique out. Definitely a fun, easy project!