Obstinacy in a sentence about a two year old

Here's a sentence that might work:

• As I tried to help my niece with her homework, her obstinacy is very frustrating.

The two-year old's obstinacy had his mother in tears. 

Iwould need the poem to you answer that

Hi! your answer would be  the women's association.  here's why:   "the childrens toys" should be "the children's toys".  there's no apostrophe anywhere, and should go after "children". it does  not go after the 's' because children is already plural, and you usually only add an apostrophe after a plural noun ends with an s, like boys or girls, for example. that is the boys' toys."the women's association", is correct.  it's kinda like the one above.  "the childrens' toys", is not correct. reason why is explained in the first one.  "none of these" isn't correct, because "the women's association" is correct.  hoped i and if you have any more questions, ask me.  -dawn