Currently there are children who learn to play only with adults.
The new generations there are families made up of only 3 members, mom, dad and son. There are children who are cared for by their grandparents and do not have the need to go to daycare and although that is also a great advantage for them, contact with other children is also important in development.
Playing with other children provides very important affective and emotional learning. The child will want the same toy as another child, and there the problems come, but they also learn to share and resolve conflicts. You will learn to listen and express yourself, to negotiate and give in. He will learn to put himself in the other’s place. In short, to socialize and generate empathy with others.