I think it's wonderful that you'd like to honour your great-aunt! How lucky for her ot have a namesake. :) However, when I see or hear Devlin, I automatically think "devilin'". I think
Devin would be a viable alternative.
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"Ye stars! which are the poetry of heaven!"--Byron
"Do not worry if you have built your castles in the air. They are where they should be. Now put the foundations under them."--Thoreau
"Music is the mediator between the spiritual and the sensual life."--Beethoven