The body of mum and dad gives the child the security they need, acting on the sensory aspect
There are children who want to stay in their arms all the time and who want to get away from their mother or father even to sleep. As soon as they are asleep their parents try to make circus numbers to put them to rest in the cradle or in the crib but often it happens that once they are laid they wake up crying.
Is this a natural behavior or a whim? In reality, according to biology, human cubs are said to be "active brought" that at birth have reflexes that predispose them to being on their parents' bodies and to be carried in their arms. The body of mum and dad gives the child the security they need, intervening on the sensory aspect. Touch, smell, hearing and sight are involved when a newborn (but also an older child) comes into contact with the body of one of the parents.
These are conditions that favor anatomical, neurological, motor, linguistic, psychic and social growth. Parents, on the other hand, often expect a child to come away from them quickly, to become rapidly independent. But this kind of autonomy is gained over time, and with direct contact. On the other hand, there are those who claim that carrying their babies in their arms is like spoiling them. Nothing more false.