The makers of Hatchimals have been working around the clock to produce more of the hatching children's toys, as they struggle to meet demand for the sold-out item that has become the hottest toy of 2016.

Spin Master spokesperson Tara Tucker says producers for the Canadian-based company are working "tirelessly" to produce more Hatchimals ahead of Christmas. "They're trickling in and they're going out as fast as they're coming in," Tucker told CTV's Your Morning on Wednesday.

The toys are Furby-like dolls that come packaged in a plastic egg. The dolls activate when the egg is played with, moving around inside until they've broken out of the shell. The hatched toys go through developmental stages, from toddler to kid.

"It's not a one trick pony," Tucker said. "Day One is not like Day Two… Week Two is not like Day Two."

The toys have become the Cabbage Patch Kids or Tickle-Me-Elmos of 2016, in large part due to the popularity of hatching videos on YouTube. Now they're nearly impossible to find at their retail price of $59.99. Instead, many are going for more than five times that amount on reseller websites.

Despite the high demand, Tucker advised parents to continue checking at local retailers for the toys. "You're better off going in store rather than online – there's more chance you'll find one," she said.

She also frowned on those who are reselling the toys at wildly inflated prices. "We don't support the inflated pricing," she said. "We want to make it reasonable and we want children to be happy over the holiday season and not disappointed."

Tucker says Spin Master didn't anticipate the toy's popularity, although they were confident in the hatching concept. "Kids are inherently curious and you've seen it with these unboxing videos (on YouTube)," she said. That led the Spin Master design team to try their hand at a toy based on the unboxing concept. "When we came up with the concept we were all excited about it," she said.

The toy took two years to design (including a full year just to develop the egg shell), and by the time it was finished, Spin Master still didn't quite realize how well it would sell.

"And then we saw the reaction from retailers who have been in the business forever," Tucker said. "That I think is when we knew, wow, this is really going to be something special."