Christmas is a time of delightful surprises — and sometimes, unexpected shocks. 

Adorable, unusual or downright scary stowaways have been caught hiding among Christmas tree branches in recent times.

Check out these "real live" Christmas tree "ornaments" that some families have had to contend with over the past few years.

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Then, share your own stories in the comments section below!

Is it a pine cone — or bugs about to hatch?

Every year around this time, people share social media posts warning about "walnut-sized" brown masses that come into households on real fir trees — masses that almost look like pine cones.

But rather than a natural decoration, these clumps actually may a praying mantis egg sack holdings hundreds of fast-growing praying mantis insects.

Daniel Reed of Burlington County, New Jersey, found a praying mantis egg sac on his Christmas tree in 2017.

praying mantis egg sac

A praying mantis egg sac is pictured. These sacs hold hundreds of babies and can come into households hidden deep within Christmas trees. (iStock)

"If you happen to see a walnut sized/shaped egg mass on your Christmas tree, don’t fret. Clip the branch and put it in your garden," Reed posted on Facebook then. 

"These are 100-200 [praying] mantis eggs!"

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His post continued, "We had two egg masses on our tree this year. Don’t bring them inside — they will hatch and starve!"

"What’s been most enjoyable is seeing how far the story has gone."

Reed still uses the same tree farm for his Christmas tree each year, even after admitting the unwelcome guests via one of the trees, he told Fox News Digital recently, calling it "funny."

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"We did find several eggs in our tree back in 2020," he also said. "None since then."

"What’s been most enjoyable is seeing how far the story has gone and how many years it keeps going," he added.

The praying mantis has an average lifespan of one year in the wild — and can grow up to 18 inches long, according to National Geographic. Their egg sacks are called oothecas.

A Virginia woman in 2019 said that more than 100 praying mantises had hatched in her home after the insects were brought in on her Christmas tree, as Fox News reported at the time.

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Molly Kreuze of Springfield told WJLA-TV that the creatures — with their bulgy eyes and angular legs — were "crawling on the walls, crawling on the ceiling. Just kind of moving."

She said the insects emerged from a brown egg-shaped case located underneath the tree's branches.

praying mantis on a leaf

A praying mantis crawls up a leaf in New York's lower Hudson Valley in July 2022. These prehistoric-looking bugs live for about one year in the wild, according to National Geographic. (Fox News Digital)

And now for another fun surprise …

How did this little owl ‘ornament’ make its way into the Rockefeller Center Christmas tree?

An owl nicknamed Rockefeller, or Rocky for short, hitched a ride inside a Norway spruce bound for Rockefeller Center in midtown Manhattan in November 2020, as Fox News Digital reported at the time. 

Rocky is an adult northern Saw-whet owl, the smallest owl species in the Northeast.

Rocky even became a literary star. She was the subject of a children’s book "Rockefeller the Christmas Owl," written by T. Troy Kolo and illustrated by Meredith Miner, the Los Angeles Times reported in 2020.

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A worker who was helping to set up the Rockefeller Center tree found the feathered stowaway. The owl was soon carefully removed from the branches, Fox News Digital reported — and she was rehabilitated at the Ravensbeard Wildlife Center in Saugerties, New York.

Rocky the saw-whet owl

In this photo provided by the Ravensbeard Wildlife Center, Ravensbeard director and founder Ellen Kalish holds Rocky the Saw-whet owl, wrapped in a little sweater, on Nov. 18, 2020.   (Lindsay Possumato/Ravensbeard Wildlife Center via Associated Press)

"Rocky might have been hiding all the way from Oneonta and, in response to the tree being transported, stayed in place as if there were predators around," Sean Beckett, owl researcher and director of natural history programs at the North Branch Nature Center in Montpelier, Vermont, told Audubon.org in 2020.

"Alternatively, she might have ended up in the tree during transportation or after it was already put up," he added. 

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"Saw-whets are migratory and it is possible that this bird was heading south over New York City, saw this large tree in a desert of concrete and went there to hide for the day."

Rocky was safely released near the rehabilitation center in November 2020.

Rocky the saw-whet owl

Ravensbeard Wildlife Center director and founder Ellen Kalish holds tree stowaway Rocky at the facility in Nov. 2020.  (Lindsay Possumato/Ravensbeard Wildlife Center via Associated Press)

Next up, a very "slick" surprise …

This slithery surprise was hiding in an Australian family's Christmas tree

A huge python — a 10-footer, to be exact — was caught slithering out of an Australian couple’s Christmas tree in 2019, Fox News Digital reported at the time.

Leanne Chapman of Brisbane said her partner went outside to videotape some birds when he turned around and noticed the snake wrapped around the couple’s Christmas tree, as she told 7News.com.au.

"It was a bit of a shock to begin with," Chapman said. "You don't really expect to see a snake in your Christmas tree."

The woman said the pair left the snake alone and went back inside — and watched it from the window. Eventually, the snake slithered away, around 10:30 p.m., as 7News reported.

snake/tree split

A python is pictured above left, and a decorated tree and some presents below it on right. In Australia, a 10-foot python slithered out of a Christmas tree and away without troubling the family further, as local outlets reported at the time. (iStock)

And now for something very cute …

Anyone want a cuddly little ‘bear’ for Christmas?

One family got an early and very cute Christmas surprise when they discovered a marsupial nestled among the branches of their Christmas tree.

When the McCormick family entered their home in Coromandel Valley, Adelaide, in southern Australia, one night, they immediately sensed that something was amiss, as Fox News Digital reported at the time

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"I think the dog went straight to the Christmas tree and was sniffing around and Mom thought that was a bit weird," said Taylah McCormick, 16, according to The Guardian. 

"There [were] baubles all over the floor … and [the dog] looked up and there was a koala in the tree."

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Their tree was fake, which was likely a bit of a disappointment for the adorable guest (see the little koala clinging to the tree in the tweet, below).

"It was pretty tangled up in the lights," the teen recalled about the koala. 

"It was a fake tree and very old, but she still tried eating the leaves off it … I saw her munch down on some, but she stopped when she realized it was plastic."

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Officials were able to capture the koala bear and soon released "Daphne," as the family nicknamed her, back into the wild near the McCormick home, Fox News Digital reported then.

Have any of your own Christmas tree "surprises" to share? Use the comments section below and let us know!