These mittens are available in a medium size. They show an embroidered design, however I do not see a chart. With that said, the design on the gloves might be all you need, or you could find another cute design.
The pattern includes instructions for a left and right mitten.
You will need a sport yarn and a #3 bone hook.
If you enjoyed this free crochet pattern, you might also enjoy more designs made available on Free Vintage Crochet.