The World of Eric Carle The Very Hungry Caterpillar Happy convertible 3 in 1 high chair is the only chair your baby will need. Based on the popular children s book The Very Hungry Caterpillar your little one will explore this wonderfully designed chair during meal time. Our ultra lightweight highchair converts between 3 stages: 1. highchair 2. booster seat and 3. youth chair that fits your little one at different ages. High Chair can fit child at 6m to 3 years; youth chair can fit child at 3 years to 6 years. The versatility keeps your child safe and secure during feeding time.