Some parents get really emotional on their child's first day of school. Here's why — and how to get through it.

The scene outside a school building on the first day classes resume can be an emotional one: wobbling chins, tear-stained cheeks and lots of throat-clearing ... and those are just the parents. As their kids head back to school — some for the first time ever — many moms and dads are sharing sentimental social media posts and reporting feeling teary and choked up watching their children mark a new academic milestone.

Those emotions are something Gayane Aramyan has experienced both firsthand as a parent — "the second he went in, I definitely had all the feelings," she says of watching her 3-year-old start preschool — and in her practice as a licensed marriage and family therapist.

"I see that all the time, that parents feel a lot of emotions, especially when it's their first child going under someone else's care and especially when they're really young," she tells Yahoo Life.

What's fueling those emotions? We asked experts to break it down.

Why emotions are running high

Starting school or moving up a grade is a positive accomplishment for kids. So why do some parents feel so sad?

"I think the emotions come from many places. One is there's some grief about your baby growing up. It's part of a grieving process of [realizing] your baby's no longer a baby," says Aramyan. She herself remembers thinking, "My baby's growing up ... he just seems so different" when her own little boy started his new school.

Parents may also be feeling helpless or overwhelmed over the "loss of control" that comes with entrusting their child to others. In the case of younger children, kindergarten may mark their first time under someone else's care; even parents who previously leaned on daycare or preschool may struggle with not having access to regular updates about what their child is doing, learning and eating all day.

"Going into a whole new setting, it's losing control," Aramyan explains. "And I think that brings up a lot of emotions, as well as the grief of time [passing] and your baby growing up."

Ulrick Vieux, a psychiatrist and the director of child and adolescent education and training at Hackensack University Medical Center in New Jersey, adds that from a psychological standpoint, "There's a number of reasons why parents will cry" during these moments, which aren't necessarily limited to parents of first-time students. For some, it might be welling up as they watch their kindergartener walk into elementary school. For others, it's sobbing on the way home after dropping their teen off at school for the first (or second or third) time.

"The first thing that we have to kind of understand is the reality of the emotional bond," Vieux tells Yahoo Life. "In many ways that can be a concern because it's basically a change in the parental-child relationship. And oftentimes there's a fear ... that you may not be able to protect them the way you used to. It's almost like this sense of a loss of control."

He adds that these transitions — from preschool to kindergarten, junior high to high school, living at home to going away to college, etc. — can prompt "a change in the dynamics" between parent and child, as well as shifts in one's identity. First-time college students who are no longer sharing a home with their families, for instance, are bound to learn more about themselves as individuals and explore new goals or interests. As they gain more independence, their parent's role changes.

"And oftentimes parents can see that," Vieux says. "But there's a concern that [parents are thinking], Well, this is not completely my journey; this is my child's journey. And there can be some anxiety regarding, Will my child make the right decisions as they develop as a human from this one stage to the second stage?"

Parents may also get overwhelmed because these school milestones — moving up a grade, graduating — bring home any particular challenges their child has overcome, Vieux adds. It's a "big deal," he notes, to see a child who has struggled with, say, illness, learning difficulties or other hardships to progress academically. "Those are tears of joy," he says.

How to get through it

Aramyan distinguishes emotional reactions at events that mark the end of a journey from those at events that mark the beginning. Crying at a child's graduation out of pride, or choking up when saying goodbye to a beloved teacher on the last day of school, for example, is a way of acknowledging that it's OK to have big feelings about closing that chapter. But when it comes to starting a new experience — one that might make a child anxious and uncertain — "it's important to show up as a calm, confident leader for our kids," she says.

In this situation, parents should focus on what their kids are feeling first and foremost, validating their emotions and guiding kids through any tears or first-day jitters. Aramyan recommends that parents go into support mode, instead of "trying to manage our own stuff, to make sure our child isn't wanting to take care of us because we're falling apart."

"It's something new and there's already so much pressure and feelings involved," she notes. "It's important for the parent to show up as calm and then manage their own emotions that are showing up after drop-off." Even parents who aren't prone to tears can benefit from taking a moment to "sit with the idea" of what changes are happening, what they signify and how they feel about it.

"Even if you're not going to cry, give yourself a moment after drop-off to really take it in," Aramyan suggests. "What does it mean for your child to grow another year older? What does it mean to let go of this control? Because a lot of times parents don't end up processing this, and so they might be carrying their own emotional triggers" around a new change like this.

Does it get any easier?

Every parent is different. Some might always be able to keep their emotions in check. Some might find the first day of school process to be unbearable with their first child, and then find it old hat by the time their second or third kid goes through it. Others might find it even harder to see their youngest child hit these milestones. Some might keep a stiff upper lip for years, and then lose it when their kid leaves for college and empty nest syndrome hits.

Vieux says that he sees a lot of empty nesters who are struggling after dropping off their kids at college. He urges them to look for silver linings, like using that newfound free time to reconnect with a spouse, travel or explore interests they couldn't before due to the demands of parenting. Parents who are reeling with the loss of control in their child's absence, he adds, can benefit from trying "to refocus on what you can control." Support systems are key, Vieux says, noting that these transitions might involve losing touch with valued school community members or parent friends as kids change classes, schools and so on.

"Do not isolate," he says. "Really make an effort to continue your social connections."

The takeaway

Aramyan says there's "no right or wrong way" for a parent to react to these school changes and milestones. Sobbing at the school gates doesn't mean you're a better mom than someone who waved goodbye to their kid and seamlessly moved on with their day.

That said, the therapist does "encourage processing feelings" during these transitions, however minor they might seem.

"If tears come, great; if they don't, great," Aramyan says. "Give yourself the time because you might be surprised what [emotions] might show up."