Leggings (views K and J) made with Simplicity Pattern 1955.  These leggings are fairly easy to make, although they could be a bit of a task for a beginner.   I altered the pattern a little bit for each pair until I feel I have a perfect copy of the pattern.

They have to be made out of stretch material.  You can buy it brand new, or recycle old stretch shirts.  If you cut the sleeves off a large T-shirt, you can make capri-length leggings and use the hem from the sleeve to make the hem for the legging legs.  This pattern comes in three sizes* for each outfit - Bratz size, Barbie and Liv size and Moxie size.  I used the Barbie pattern first, but found it to be a bit too tight, so I switched to the larger Moxie doll pattern and found it a better fit.

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*Doll clothes in three sizes:

S - 10-1/2" (26.5cm) Bratz Dolls

M - 11-1/2" (29cm) Barbie and Liv Dolls

L  - 12-1/2" (32cm) Moxie Fashion Dolls