I have known sorrow — therefore I
May laugh with you, O friend, more merrily
Than those who never sorrowed upon earth
And know not laughter’s worth.

I have known laughter — therefore I
May sorrow with you far more tenderly
Than those who never guess how sad a thing
Seems merriment to one heart’s suffering.

Theodosia Pickering Garrison (1874-1944) American poet

“Knowledge,” The Century Magazine (1900-08)
    (Source)