For her 21st birthday celebrations last week, she debuted a dramatic beauty transformation - flaunting platinum blonde ... white cropped t-shirt with a pair of light-wash denim jeans adorned ...

On brand, she stuck to her understated MO to attend yesterday’s gathering and wore a simple white top. Hers, however, was spicy — it featured a cropped ... paired it with jeans from Mango.

Sienna oozed It-girl glamour in a cropped leather top with a sleeveless silhouette and zip-up fastening, paired with low-rise turned-up white barrel jeans that showed off her toned midriff.