They are the children who want to fly, but that she cannot give them.

She cannot give them, the children, what they want: flight

They are the children who want what she cannot give them: to fly.

She doesn't want to give them flight, which is what they cannot do.

They are the children who cannot fly because she does not want to give them that.

She cannot fly, so they want what she cannot give.

They cannot fly, so she wants to give them that.

She doesn't want the children, so she cannot give them flight.

They don't want her to give the children the ability to fly.

She doesn't want not to be able to give them flight.

The children don't want not to be able to fly because of her.

If she wanted to give the children flight, they, the children, would not be able to recieve it.

If the children wanted flight, she would not be able to give it.

Do they?

Because they, the children, want to fly, she cannot give it to them.

Because she wants to give them flight, they, the children, cannot receive it.

Because one wants to give flight and the others, the children, to receive it, they cannot. No one achieves flight. Not she, not the children, not ever.