A row has broken out in Germany about what should happen to a polar bear cub that was rejected by its mother.
Knut is being looked after by keepers at Berlin Zoo, but some animal rights campaigners say it's unnatural and it would have been kinder to let him die.
Knut was born in December. When his mum ignored him, zoo keepers decided to help him out by feeding, bathing and exercising him just like other babies.
But some experts think being raised by humans will do him more harm than good.
Frank Albrecht, who's an animal rights campaigner, started the row when he told a German newspaper the zoo should have let Knut die, because that's what would have happened in the wild.
Although polar bears might look cute and cuddly when they're young, they grow up to be fierce and frightening predators.
Campaigners say Knut needs to learn how to behave like that in the wild so he can fit in with other polar bears, if he needs to.
A spokeswoman for the RSPCA said: "Unfortunately with hand rearing there's a lot of problems that can lead to behavioural problems later in life.
"It's a tricky situation and the zoo's going to have to decide what to do."
But zoo bosses say they have no intention of putting Knut to sleep and even think it might be better for him to be raised in captivity.
That's because polar bears are an endangered species - there are only about 20-25,000 of them left in the world - and looking after them could increase their numbers.
Berlin Zoo's vet said: "Knut was a healthy baby bear when we found him and so there was no reason for us to put him down. And there's certainly no reason to do so now."