The phrase means "Do you have children?" Your answer would be "Sí, tengo....hijos" or "No, no tengo hijos".
It is "¿Cuántas hijos tienes?"
Translation: Tienes hijos?
"¿Tienes hijos?" would be the way to say "do you have children?"
¿Cuántos hijos tiene / tienen / tienes / tenéis?
"Primos tienes" means "Do you have cousins?" in Spanish.
tienes
¿Tienes?
"Tienes una novia" means "Do you have a girlfriend" in Spanish.
"Tienes" is the second person singular form of the verb "tener" in Spanish, which means "to have." It is commonly used to express possession or obligation.
have have
"You have" is "tienes".
tienes