From "Star Trek: The Next Generation: Family (#4.2)"
CPO Sergey Rozhenko, ret.
[about Worf as a child
] So we walk into the school, and we didn't know what to expect - is Worf hurt, is he in some kind of trouble? The door opens, and there is our little seven-year-old sitting on a chair and glaring across the room at five teenage boys, all of them with bloody noses!
And then the principal looked up and said, "Please, tell me he's an only child."