Once you have a baby it seems like all you can think about in your sleep-deprived mental state [1] is about when your baby is going to achieve milestones. When will tummy time result in their first solo roll? When will they start smiling in response to your voice? When will they begin pulling at anything and everything to help themselves stand, really putting your baby-proofing skills to the test?

It's easy, especially as a first-time parent, to get nervous about where your child is on their developmental timeline, and it's even easier to compare them to other children and convince yourself that something may be wrong because they aren't moving as fast as their pint-size friends. To help calm our nerves and give us some insight into the business of milestones, we spoke to Dr. Deena Blanchard, a pediatrician at Premier Pediatrics in New York City [2].

Read through for the three things you need to know about your baby's developmental milestones [3].

Every Milestone Occurs During a Time Period, Not at an Exact Time.

“I think it’s really important for parents to remember that development is a continuum,” Dr. Blanchard told POPSUGAR Moms. "Let’s take sitting as an example. Most babies will sit on their own somewhere between 6 and 8 months. Some will do it at 5 months, some will do it at 8 — it’s not necessarily better to do it at an exact time. As long as they’re doing it within the general continuum of normal development, that’s OK. I think that’s a really important message because parents get stressed out thinking that their child has to do specific things at an exact time, but all developmental milestones happen in a time period."

When you go to appointments with your child’s pediatrician as they grow, they’ll be closely evaluating your child based on that short visit combined with your answers to their developmental questions. If your child isn’t hitting milestones within the suggested time ranges [7] and you’re concerned, talk to your child’s doctor about the next steps, whether that involves waiting a few more weeks for organic success or discussing early intervention or therapy options.

You Shouldn't Let Your Friends’ Kids Be Markers For Your Child’s Successes.

Although the idea of keeping up with your friends’ children’s achievements could seem like a good way to keep tabs on your little one, it’s not always healthy to compare. “I don’t like that between parents when they’re like, ‘Ooh, my child started walking at 11 months,’ you know? You don’t want to do that," Dr. Blanchard says. "In general I encourage people not to compare their children to their neighbor's children because you're just going to stress yourself out."

Every child moves at a different pace and needs to figure things out in their own time and at their own speed. "If you are freaking out, though, channel your energies to your pediatrician and check in because it’s their job as an expert to let you know if something’s not going the right way. Ideally, a pediatrician is screening at every visit and checking on everything, but if you’re still worried, check in."

You Shouldn’t Ever Feel Bad About Your Child Having Any Type of Delay.

“There’s this whole sense of comparing things that don’t necessarily deserve to be compared,” Dr. Blanchard says of parents who may feel shame because of their friends sharing information about what their child is achieving. "What if someone’s child is delayed? Why should they have to feel bad about that? It’s OK. They should feel like they’re great parents because they picked up on it with their pediatrician and addressed the issue."

A note to parents who had their babies prematurely: "Premature infants — any baby born before 37 weeks — need to be corrected for their development. Let's say a baby is born at 32 weeks gestation. Technically they're entitled to eight extra weeks for the first two years of their life to meet developmental milestones. They may do everything 'on time,' but they're entitled to the extra time and that's important because you don't want to compare a baby born at 32 weeks at 16 months of age to a baby born full-term at 16 months of age."