I need help! Can anyone help me find the author of the following poem fragment?

“There are things of which we may not speak;
There are dreams that cannot die;
There are thoughts that make the strong heart weak,
and bring a pallor to the cheek,
And a mist before the eye.
And the words of that fatal song come over us
like a chill--
Your will was the wind’s will,
And the thoughts of youth are long, long thoughts.”

I need it soon for a memorial my family is publishing to my sister who died last year. Thanks!

It's from My Lost Youth, by Henry W. Longfellow

[www.cs.rice.edu] />
Les