Your toddler is not yet 2, and still he's acquired so many new skills. He walks with confidence, perhaps even outrunning you on the playground and adding a hop here and there. He can push and pull his toys and discovers that he doesn't have to crawl up the stairs because he can reach the railing and walk up or down them like you do. He's becoming a master climber, too, which means he can get into almost anything, even if he has to use the stool in the kitchen to get to the forbidden object. In fact, by day's end you might be ready to crash on the couch with a magazine, but your toddler is still on the go. Sometimes you can't help but wish he had an off switch!

Your toddler's constant motion is doing a lot more than building her muscles (although she is getting a workout!). For instance, walking, running, and climbing on different surfaces helps develop spatial awareness, hand-eye coordination, and balance. At the same time, she is learning about actions and consequences as she solves problems along the way, like how full she can fill a laundry basket with stuffed animals before it's too heavy to carry -- and what will happen if she drops it.

Your child is continuing to hone his fine motor skills during this critical period of development. Between 19 and 21 months, he can probably stack up to six blocks to build towers, and he loves scribbling on paper (or on the walls) with a crayon or marker. "Don't expect them to sit still for long with crayons in their hands, though," says Ari Brown, MD, coauthor of Baby 411 (Windsor Peak Press). At this age, it's the process of drawing -- dragging the marker across the page to make a bold line -- rather than the finished product, that's important to them.

Soon after her second birthday, she may begin to add curves, angles, and corners to the lines she draws. Those crucial changes in direction indicate that your toddler might be attempting to draw a picture that represents something real, though you'll have to ask what it is. It won't be until your child's third birthday that she will be able to draw simple pictures that an adult might recognize as a person, a tree, or a house. In the meantime, enjoy your toddler's scribbling as one more major milestone in her physical and intellectual development.