"¿Cuántos hijos tiene ella?"

This questions sounds more like asking how many kids she has, not sons

"Boys" would be ninos. Hijos is "sons" or "children".

boys would be ninos <-- (english keyboard no accents) rather than hijos

Ya bro

Subjects typically go after the verb in Spanish questions: http://spanish.about.com/od/sentencestructure/a/sentenceorder.htm

Without context, you don't. It could mean either.

In a real-world situation, you would have the context you need to know that..

If not? You could get more information..

But here we are just translating sentences to get a sense of sentence structure while building vocabulary.

It would be understood but the syntax is odd to a Spanish speaker.

I think so.

Check out Neiht20's hyperlink.

Because with out the assent mark, the meaning changes from how much, or how many to "as much as" example: cuanto (adverb) = as much as - Example: Come cuanto puedas. Eat as much as you can.

The accent signifies it as a question word as opposed to one that is used in non-question contexts. Compare: cuánto vs. cuanto, cómo vs. como, que vs. qué and so forth.

@dkat - re: ...stress when it would stressed naturally?

Hola dkat. You noticed something very important. The Spanish language has accent marks that serve different purposes. In the case of the accent marks that you noticed, they fall on the part of the word that is naturally stressed. So they can't change anything regarding the pronunciation. So why are they there?

In this case, the accent marks are called orthographic accents. Check out this hyperlink.

http://spanish.about.com/cs/writing/g/orthoaccgl.htm

"Got" is used in a lot of informal contexts in English, it's not technically correct, but it's pretty common. "Got" is used many times in place of "have", so some may say "how many kids does she got?", but it's better to say "have".

The verb is tener (meaning 'to have'), the ending changes depending on who you are talking about. _use tengo for 'I' _use tiene for 'he/she/it/you (formal)

The helping verb "does" is missing and "has" needs to be "have".

"How many sons does she have?"

If we add the sentence structure, "How many sons (children) does she have?" to this list, does any one of them break an English grammar rule.

What sounds correct to one person is subjective and varies from place to place in the larger English speaking world.

It's best to base the correctness of sentence construction on rules of grammar which are objective.

Hijos can refer to only the male offspring of a particular person or the combination of male and female offspring of a particular person. There is a lot of information in the word hijos.

Niños refers to male children in general or male and female children in general. We don't get the extra piece of information about the parent.