You don’t have to knit long pants, shorts or leggings would be great, too.
You can even make the face look however you want. Choose a familiar character of kids favorite, or go wild and come up with something personal and original.
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You can also knit and add yarn pom pom as big nose to make Elso pants as seen on irarott.com, kids would love it. Etsy has some inspirations of knit elmo pants to knit after or purchase. Irarott also has a crochet owl pants that make kids looks like owlets.
Paid Pattern: crochet owl pants
Here is a crochet version of baby monster pants video tutorial for your guide, good luck and have fun there.
Youtube: Fuad Azmat / YARNutopia by Nadia