Thumb Wrestler's Sweaters - A free pattern

We've been trying to find ways to discourage a bad habit. To that end, the Thumb Wrestler's Sweaters were invented!
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Pattern:

Needles: 3.25mm dpns

Yarn: worsted weight

Size: to fit 9 year old thumbs

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Cast on 10 sts using the backward loop method. Join and knit in the round for 7 rounds. To keep the cast off edge stretchy, knit 1, *slip it back to the left hand needle, k2tog*. Repeat from * to * until all the stitches have been cast off. Break yarn and weave in ends. Repeat if you wish to have a sweater for each thumb.

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M was hesitant for me to share this pattern until he realized it might help others to not suck their thumbs too.
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