O's old clothes are now being worn by her little sister, C2. Unfortunately, little man C1 doesn't have quite as many options. There's the unisex onesie here and there, but nothing that's worth mentioning.There are some good brands out there that make nice pieces for boys, without making them look like little prepsters. Tea Collection, for example, makes graphic cotton separates that can be mixed and matched. The Daily Tea Collection is perfect for everyday wear and tear.
Another brand is Appaman. The graphic tees and onesies are "street-worthy" and not cutesie. Both brands also offer girl clothes that are sweet and easy to wear.