You should always choose a step stool that has a proper surface grip to prevent slipping. The surface that your toddler will stand on should not be a slippery surface and should have a proper grip to maintain balance. When your step stool comes with non-slip grips on the feet, your step stool will be able to stay in one place. Be sure when researching step stools online, that you checked the specifications listed to make sure it comes with a non-slip feature.