Sealy Soybean Natural Dream is our best-selling baby crib mattress featuring a natural soybean foam-core for extra-support. Lightweight and hypo-allergenic, the baby mattress offers a breathable and soft cotton cover that is waterproof and stain-resistant for easy cleaning. More babies sleep on a Sealy than any other brand in the USA. Sealy proudly supports infants and toddlers with industry-leading crib mattresses known for safety, quality, comfort and premium support. CertiPur-US approved foam. Size: Standard Crib. Gender: unisex.