GEOFF BENNETT: And now a lighter story to end the week.

In a zoo outside Tokyo, one monkey has pulled heartstrings around the world after forming an unexpected friendship.

Stephanie Sy has the story.

STEPHANIE SY: It's a story of rejection, vulnerability, and the animal instinct for companionship.

It helps that the central character is an terribly cute monkey, a seven-month-old macaque in Japan's Ichikawa City Zoo named Punch.

Abandoned by his own mother shortly after birth, zookeepers handed Punch a stuffed animal.

Never mind that the orangutan is a different species, he's hardly let go of it since.

KOSUKE SHIKANO, Zookeeper (through translator): This soft toy has quite long fur and several easy places to hold.

And it looks like a monkey.

We thought that it looking like a monkey might help Punch integrate back into the troop later on.

STEPHANIE SY: Watch as baby Punch is dragged around like a chew toy, escaping to the comfort of his protector, using him for cover.

Videos like these have sparked an outpouring of love and sympathy from the more evolved primates among us.

WOMAN: Nobody wants to be a friend.

STEPHANIE SY: But he has plenty of friends on TikTok.

#HangInTherePunch has gone viral.

The spectacle has drawn massive crowds to the zoo, and there's a run on the stuffed animal at Ikea.

MIYU IGARASHI, Nurse (through translator): He's become such an idol-like figure already, so I hope he stays lively and continues being an idol.

ALISON BEHIE, The Australian National University: It's not by any means a replacement for a mother, and it's not going to give the animal the attachment that it sort of needs in order to develop.

But it does give sort of an avenue to retreat to that might in the moment reduce those stress responses a little bit, allowing him to feel a little bit less of that anxiety and stress.

STEPHANIE SY: Alison Behie is a primatology expert at Australian National University.

She says the other monkeys' ornery attitude toward Punch tracks.

ALISON BEHIE: Japanese macaques, they live in very strict matrilineal dominance hierarchies, which means there are dominant families and there are subordinate families.

Dominant animals show aggression.

Subordinate animals respond appropriately with sort of a subordinate signal, and then everyone stays happily in their place in the hierarchy.

So while it does look like bullying, and it looks quite confronting because it's an infant and because their mother has rejected or abandoned them, it is just a sort of a normal part of a macaque society to have that sort of aggression as normal social behavior.

STEPHANIE SY: But there are reasons to hope.

More recently, Punch seems to have made a breakthrough.

He's starting to make actual monkey friends and taking cues from adult monkeys on how to shelter from the rain.

ALISON BEHIE: It's actually really reassuring that Punch is already sort of shown -- being groomed, being integrated into the group's structure, because it does suggest that hopefully any potential negative impacts of the abandonment will in fact sort of dissipate.

STEPHANIE SY: Zookeepers say Punch is showing signs of resilience.

KOSUKE SHIKANO (through translator): It depends on how Punch is confidence develops going forward.

But, recently, he's been spending less time with the stuffed toy day by day, and he's interacting with the other monkeys more.

If things carry on like this, I think there will come a day when he no longer needs his stuffed toy.

STEPHANIE SY: As cute as their relationship is, they will know Punch is really OK when he finally gives up his beloved surrogate.

For the "PBS News Hour," I'm Stephanie Sy.