Nice dry fit material! They are lined so will
work well in cooler weather. Bought my son a size 7, they are a little big but for me
personally I would not size down as kids grow so fast and after many washes the material could slightly shrink. My son is 5 years old, 50lbs and 47 inches tall. Size 6 would have been a perfect fit but not much room for growth. These run true to size.