For Greg Clapp, it felt like a switch had flipped. Six weeks ago, Clapp’s son, Nolan, went from being a content, even-keeled soon-to-be 2-year-old to a toddling ball of nerves — almost overnight.

During routine family walks around the neighborhood, Nolan, usually perfectly happy around new people, started running to his parents, whimpering to be picked up and held whenever a stranger passed. At bedtime, Nolan started attaching himself to the nearest parent, shrieking if his mother or father left the room even for a few minutes, and wailing as he was put down for bed.

Since then, the anxiety hasn’t let up, leaving Clapp and his wife scrambling to find ways to help their son cope when they step away.

“We’re just trying to let him know that when he’s in our house, it’s a safe place whether Mom and Dad are there or not,” said Clapp, a stay-at-home father based just outside of Milwaukee. “We’re always there for him if he needs us.”

Separation anxiety is normal and happens as children begin to differentiate between things that are safe and familiar and things that are new and different. Classic symptoms include clinginess when a parent or caregiver is present, and crying or short tantrums right after the person leaves the room or home.

For most kids, separation anxiety sets in between 8 and 12 months of age and fizzles out around age 3. But for kids who have a condition called separation anxiety disorder, which affects between 3 and 5 percent of children, those meltdowns can persist into elementary school and even after. They may escalate over time and include physical symptoms such as headaches, stomach aches or bowel problems.

The current pandemic has added an extra layer of stress and disruption. Symptoms might increase, especially in households where one or more parents are essential workers who are now home less often, and strategies for dealing with separation anxiety episodes may be harder to execute.

Research shows that there is a right and a wrong way to handle separation anxiety episodes, and there are distinct signs that indicate when parents should seek medical help.

Anxiety often has a negative connotation, but it’s a crucial protective mechanism that children begin to develop during their first year of life, said Karin L. Price, Ph.D., the chief of Psychology Services at Texas Children’s Hospital in Houston.

Healthy anxiety warns us when danger might be ahead, and for babies and toddlers, separation anxiety marks a developmental milestone as children begin recognizing that loved ones offer the most safety and protection. “It’s evidence of secure attachment to caregivers or to parents,” Dr. Price said. When children 12- to 18-months-old don’t show any distress when separated from loved ones, “that’s when we’re actually more concerned.”

Short, manageable meltdowns that happen right after day care drop-off, at bedtime, or when a parent leaves the room are normal and generally self-limiting, Dr. Price added. Those episodes can also happen during periods of transition, such as after moving into a new home or starting a new school. They typically last only a few minutes and go away entirely after the child has had a few weeks to adjust to the new routine.

But meltdowns that drag on, persist month after month, or escalate to the point of interfering with the child’s ability to do age-appropriate activities could be signs of a more complex problem, said Eli R. Lebowitz, Ph.D., director of the Program for Anxiety Disorders at the Yale Child Study Center.

Separation anxiety disorder is the most common anxiety disorder in children ages 12 and younger, and symptoms can emerge as early as age 2. The causes aren’t entirely clear. Genetics play a role — if one or both parents have an anxiety disorder of any kind, their children are more likely to have separation anxiety disorder. The disorder can also be triggered in the wake of a stressful life event, like the death of a loved one, Dr. Lebowitz said.

As the coronavirus isolates families and disrupts daily schedules, it’s not always easy to know if a child’s anxiety is the result of quarantine and will disappear once life gets back to some version of normal, or if it’s a symptom of separation anxiety disorder.

Erin Siraguse, a mother of three in Burke, Va., is searching for answers for her 5-year-old son, Beckett. Last summer, after the family’s beloved nanny moved away, Beckett became clingy and started crying whenever Siraguse left the room.

Siraguse gave birth to her third child in December. Then the pandemic hit, eviscerating daily routines and social activities. Beckett’s episodes worsened. Instead of just crying, Beckett screams, throws himself on the floor, and can’t calm down unless he’s held and rocked. “I’ve never seen anxiety like his before,” Siraguse said. Beckett is being evaluated for anxiety disorders and attention deficit hyperactivity disorder.

Parents who are concerned that their child may be showing signs of separation anxiety disorder should see a therapist who specializes in treating pediatric anxiety as early as possible, Dr. Lebowitz said. If left untreated, anxiety disorders increase the risk of other mental health conditions such as depression. Treatment generally involves using cognitive behavioral therapy to help kids learn to manage symptoms plus training to help parents manage tantrums.

De-escalate meltdowns and prevent future ones

There are also evidence-based strategies that all parents can use to try to prevent or de-escalate meltdowns that come from separation anxiety. When children are calm enough to listen, validate their feelings by acknowledging that you understand why the situation makes them feel scared, and encourage them to practice being brave and trying an activity on their own. This strategy takes time and patience, but it’s more effective in the long term than giving in and trying to stay within children’s eyesight or allowing them to avoid situations involving separation, said Golda Ginsburg, Ph.D., professor of psychiatry at the University of Connecticut School of Medicine.

“If you are always rescuing your child from anxiety-provoking situations, they never learn that they can master the situation on their own,” Dr. Ginsburg said. Parents can also inadvertently make separation anxiety worse by prolonging goodbyes and paying attention to tantrums, and forgetting to reward quiet acts of bravery, like playing alone or going to bed without fuss.

Finding opportunities for children to exercise their “brave muscles” and safely practice being away from their parents is especially tough in quarantine, said Paula Yanes-Lukin, Ph.D., director of psychology in the Children’s Day Unit at the Youth Treatment and Evaluation of Anxiety and Mood Program at Columbia University. If you suspect that your child might struggle with an upcoming event, like starting remote learning, returning to preschool or an overnight visit with family, practicing the routine a few days before can help your child prepare.

You can also teach your kids strategies they can use in situations that make them anxious, Dr. Yanes-Lukin added. One way is by giving them a transitional object — something small and personal that reminds your child of home — that they can keep in their pocket or cubby and retrieve when they need to feel a connection to loved ones.

Kids aren’t the only ones with tension. Anxious parents can exacerbate their children’s anxiety, so take steps to relieve your own stress, too. Sean Leacy, a father of four in Tacoma, Wash., takes a holistic approach to managing anxiety in his house. Two of Leacy’s children exhibit separation anxiety symptoms and have been diagnosed with sensory processing disorders. Leacy has stress management strategies individualized to each child, but he also credits City Dads Group, a nationwide parenting support group for fathers, for helping keep his own anxiety and parenting stress in check.

“It’s an opportunity for dads to hear that they’re not alone in it, which is so easy for us to feel like, especially during pandemic,” he said.

The separation anxiety phase can be tough on children and equally tough on struggling, frustrated parents who are trying to help their kids make it through an exceptionally hard year. There is one silver lining, said Dr. Lebowitz. “It passes.”