Source : Webster's Revised Unabridged Dictionary (1913)

Sweetly \Sweet"ly\, adv. [AS. sw[=e]tlice.]
   In a sweet manner.

Source : WordNet®

sweetly
     adv : in an affectionate or loving manner (`sweet' is sometimes a
           poetic or informal variant of `sweetly'); "Susan
           Hayward plays the wife sharply and sweetly"; "how sweet
           the moonlight sleeps upon this bank"- Shakespeare;
           "talking sweet to each other" [syn: {sweet}]