Answer:

onlychild

Answer	Crossword Clue
ONLYCHILD	Single issue?
ONLYCHILD	Kid with no siblings
ONLYCHILD	Spoiled brat, stereotypically

ONLYCHILD	One sans siblings
ONLYCHILD	Person with no siblings
ONLYCHILD	One with no siblings
ONLYCHILD	One without siblings
ONLYCHILD	One without siblings.
ONLYCHILD	Member of a small family
ONLYCHILD	Eloise of Kay Thompson books, e.g.