It sounds like you're referring to a "Stego Roar" boy's short set, which is likely a children's clothing set featuring a design, possibly related to dinosaurs, with "Stego" referring to a Stegosaurus and "Roar" hinting at the playful or dinosaur theme.
These sets typically include a t-shirt or top with matching shorts, designed for comfort and casual wear. They are often made from lightweight fabrics suitable for warm weather and feature fun graphics, such as dinosaur images or prints, making them appealing to young boys.