Boy playing with a Model Railway (Bulgaria 1989)

Stamp Boy playing with a Model Railway it reflects the thematic directions:

Biologically, a child (plural: children) is a human being between the stages of birth and puberty. The legal definition of child generally refers to a minor, otherwise known as a person younger than the age of majority. Child may also describe a relationship with a parent (such as sons and daughters of any age) or, metaphorically, an authority figure, or signify group membership in a clan, tribe, or religion; it can also signify being strongly affected by a specific time, place, or circumstance, as in "a child of nature" or "a child of the Sixties". There are many social issues that affect children, such as childhood education, bullying, child poverty, dysfunctional families, child labor, hunger, and child homelessness. Children can be raised by parents, by fosterers, guardians or partially raised in a day care center.

Play is a range of intrinsically motivated activities done for recreational pleasure and enjoyment. Play is commonly associated with children and juvenile-level activities, but may be engaged in at any life stage, and among other higher-functioning animals as well, most notably mammals and birds.