The reason why the mother cat carried the kitten away and hid it:
1. A mother cat hides her kittens because she doesn't trust her surroundings and is worried about danger.
2. This is a mother cat's instinct; to protect her kittens from harm, they will choose to hide them. 
3. After giving birth, mother cats are very weak and irritable. They will hide their kittens so that they can have a quiet postpartum period without being disturbed.
4. After giving birth, the mother cat will also need to go out to find food, so she will hide her kittens when she goes out to find food.
5. It's possible that the mother cat wants to find a male cat to help care for the kittens, so she carries the kittens to a male cat to take care of them.
Solutions when a mother cat takes her kittens away and hides them:
1. If there are other cats or animals in the house, separate them from the mother cat to make the mother cat feel safe.
2. You can put the kittens in the nest when the mother cat isn't looking, or you can prepare a relatively quiet and secluded place for them.
