Whose side do you think Wordsworth is on? Does he agree with the little girl or with the speaker?

I think that Wordsworth understands the girl. As Wordsworth begins to consider his own mortality memory is again a huge comfort, because he realizes that even after he has died he will be able to live on in the memory of his family and friends, just as those who have passed on before him are in his memory. Wordsworth is especially heartened to know that his sister Dorothy, with whom he spent countless hours, will remember him fondly, carrying him with her wherever she goes.