She helped Tommy by her helplessness.

There is reason to believe that once in London, when she had need of a new hat, but money there was none, Tommy, looking very defiant, studied ladies' hats in the shop-windows, brought all his intellect to bear on them, with the result that he did concoct out of Elspeth's old hat a new one which was the admired of O.P.Pym and friends, who never knew the name of the artist.

But obviously he could not take proper care of himself, and there is a kind of woman, of whom Grizel was one, to whose breasts this helplessness makes an unfair appeal.

Oh, to dress him properly! She could not help liking to be a mother to men; she wanted them to be the most noble characters, but completely dependent on her.
Tommy walked home with her, and it seemed at first as if Elspeth's absence was to be no help to him.

He could not even plagiarize from "Sandys on Woman." No one knew so well the kind of thing he should be saying, and no one could have been more anxious to say it, but a weight of shyness sat on the lid of Tommy.