Layers are always in, no matter the season. In fall and winter, you warm up with scarves, sweaters and jackets -- and in summer, layering thin tanks and light scarves adds styling without bulk. But in late spring, when the temps can swing, the celebs have been spotted adding layers to their jeans ensembles for style and comfort.

And while they may be moms of multiple kids, Reese Witherspoon and Sarah Jessica Parker never sacrifice fashion for function.

Witherspoon's layers and jeans were super menswear-inspired, thanks to her hat and boyfriend jeans. She kept it femme with a pink top and leopard-print ballet flats.

Pacific Coast

SJP, who has twin daughters and a son, piled on the layers with a top, a split zipper hoodie and a light knit cardi. Notice that the queen of Manolo Blahniks does wear sneakers, albeit platform ones. The best thing about this look is that she can add and subtract as needed or as the weather dictates.

Pacific Coast News

Actress and new mom Sienna Miller did summery layers above the waist with tank tops. The bright red ankle booties and light wash jeans kept her look fashionable, as did the suitcase-sized bag.

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Jessica Alba, who has two daughters, has layering down to the science. With her voluminous top and wide-legged jeans, the addition of a scarf was all she needed.

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