It wasn't super easy to find a simple crochet cardigan sweater pattern in a girl size. But I knew I would find what I was looking for in the vintage pattern section of etsy. This pattern booklet was so 80's, it was perfect.
It was just a few different panels (front sections, back, sleeves), then weave them all together. The yoke was last with the color contrast.
I told the girls "it's just one stitch after another, then pretty soon, it's a sweater!"