Light weight sport yarn 3 conversion to crochet thread

I am wanting to make an infant dress that calls for light 3 worsted weight. I would prefer to use crochet thread. Does anyone know if 3 thread would be equivalent? Thank you.

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There is 3 wt crochet cotton. You will need to check your gauge. Also the feel and drap will be different using a cotton rather than acrylic. Make a swatch of each to compare.