Is my child a hoarder?

“Moshwhat?” I asked my son Adam when he declared last year, at age six, that he wanted to collect Moshi Monsters toys. Moshlings, I have since learned, are cute plastic figurines, each with their own specific talents and personalities, and just one of the many collectibles marketed to school-aged children. Suddenly, Adam wanted to know all about these unusual creatures, researching the different types and talking about them with friends. It almost felt like he’d joined a cult.

But collecting — whether it’s dolls, stickers or rocks — is a natural stage of child development. It lets young minds exercise their rapidly improving abilities to analyze, group and classify objects, and it can also provide a sense of self.

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“At this age, kids realize they can have an identity of their own, separate from their parents,” says Aviva Golberg, a child behaviour therapist in Toronto. “They realize, ‘I can have my interests and identity, and here’s something I have ownership of, and that I care about.’”

Kids may also collect in order to feel like they belong to a group. That’s how Lili Senman’s son, Eli, 7, starting collecting hockey cards last year. “An older friend was really into it and now it’s their ‘thing’ together,” says the Toronto mom. Eli has two binders with hundreds of cards and enjoys trading them with friends. “Kids always seem to need a ‘thing’ to talk about — and hockey cards are a cheap and easy interest.”

Because children often become emotionally attached to their collections, parents play a role as well, says Golberg. “It’s important for parents to take an interest and become knowledgeable about the topic, too.” As you prepare to navigate the intricacies of Moshlings, Beanie Boos or Rainbow Looms, here are a few things to keep in mind:

Be cool, but set limits You may not be thrilled with your child’s accumulation of what might otherwise be called junk but rest assured, it’s not actually a gateway to hoarding. Kids must learn that they can’t get everything they want, so they should save up their allowance to buy collectibles or earn them some other way. “Aside from birthday or holiday gifts, Eli has to earn his hockey cards by doing things we want him to do, like reading or brushing his teeth properly,” says Senman. Even when kids collect items that are free, such as rocks or stamps, make sure it’s not taking over their other likes, says Golberg. Similarly, if a collection seems to make a child anxious or he starts to feel he needs “all of them” to feel complete, parents should step in and seek help if necessary.

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Let them sort it out Find a binder, box or other container kids can use to organize and showcase their prized possessions. But stop short of sorting the items yourself, Golberg advises. “Part of what they want to do is explain to someone else why they’ve grouped certain things together. If you’re too involved, it won’t be as fun for them.”

Be a research assistant Sport or trading cards have stats and other data built right in, but for other interests, help kids find books, websites or other resources so they can learn more about their topic of choice.

Stay out of trade disputes Sure, your child may swap an item and regret it later. But resist the urge to negotiate a return. “Remember when we were kids we would say, ‘No trade backs?’” says Golberg. “This is an important life skill they need to learn — I’ve made a deal and I can’t get it back.”

What if your child never starts a collection? Don’t worry; it often boils down to personality, Golberg says. Senman would agree. While research shows that girls are just as likely as boys to keep some kind of collection, her daughter Evan, 5, doesn’t collect anything. Eli, on the other hand, has added a Pokémon binder to his hockey-card assortment. And — surprise — my son Adam is now collecting them, too.

We asked... Are your kids obsessed with collecting a specific kind of toy or object? We asked our readers and found that rocks, acorns and snow globes were the most sought-after treasures. The weirdest answers? Dead wasps, sand and business cards.

A version of this article appeared in our December 2013 issue with the headline "Hoard alert," p. 88.