A child must be your child, step child, adopted child, foster child, brother or sister, or a descendant of one of these (for example, a grandchild or nephew).
As a broad theory, symbolic interactionism appeared in the 20-s of XX century, in the Chicago school, its founder was an American sociologist George Mead. George Herbert Mead (1863-1931) is an American sociologist and social psychologist, who is considered a true founder of symbolic interactionism.
Symbolic interactionist researchers investigate how people create meaning during social interaction, how they present and construct the self (or identity), and how they define situations of co-presence with others.