Most parents already know to look for the much-lauded ones, like rolling over and walking. But of the multitude of milestones cited by the American Academy of Pediatrics, some are considered more significant. Here, 10 milestones that are worth paying a little extra attention to during your child's first two years:

1. Eye contact
(between 6 and 8 weeks)

This is one of the first milestones you'll notice, and it's a big deal not just because your baby is finally paying attention to you, and following you with her eyes, but also because it indicates that her neurological growth and ability to communicate are on track. She's demonstrating that her brain is registering a familiar face. In a sense, she's saying, "Hey, I know who you are."

Laura Weber was worried when, at 4 weeks, her infant, Nicole, never met her gaze. "Whenever I tried to make eye contact with her, she'd look over my shoulder instead," says the mom of three from Fredericksburg, Virginia. Fueling her concern was the fact that her first daughter, now 4, hit all the milestones on the early side of "normal." When Weber voiced this at Nicole's checkup, her pediatrician stressed that with milestones, there's a wide range of normal. Indeed, Nicole reached this one at 3 months, the late side of normal.

If Nicole hadn't begun to make eye contact after 3 months, her doctor would have suggested vision testing to rule out eye disease. The next step would have been to look for signs of attachment or behavior problems. But experts urge parents to refrain from jumping to the worst-case conclusion. "You have to be very cautious about assuming your child has a certain condition. It has to be taken in context with so many other things," says Martin Stein, M.D., director of developmental-behavioral pediatrics at Rady Children's Hospital San Diego.

The more likely reason for no eye contact is that you're looking at the wrong times. "An infant needs to be in a quiet but alert mental state to respond in this way, and most of the time an infant is awake she's tired or hungry," says Dr. Stein. The lesson? Be patient, and keep your eyes open.