As a rule, from 4-5 weeks to 1.5 months, the kittens are in a small enclosure, where they only learn to walk, eat and start using the pot. In 1.5 months they are transferred to a specially equipped room for kittens. It can be a glazed loggia of a large size. In 1.5 months it is undesirable to let the kittens go free.
We need to continue to monitor how they go to the toilet, whether they add weight. In addition, this is the time of vaccination and de-worming. So, kittens should always be in sight. If you release them into an apartment, you will not be able to establish proper control, and you will never know in time how the kitten feels after vaccination. He can get under the sofa, and while you find him, precious time will be missed.
There is an opinion that non-friendly kittens grow because they are kept in cages and they do not get to communicate with a person. Unfortunately, everything is not so simple. Even if you constantly strok the kitten, try to replace his mother cat, the kitten will not become affectionate if the genetics dictate to him another. Affectionate are kittens who have a calm, steady psyche. Such babies are not prone to stress, they easily tolerate moving and introducing complementary foods. They can be transported to exhibitions. This, they say, animals with show temperament. But that the kitten was affectionate, at least it is necessary that the same character was at least one parent.