Create harmonious melodies following the given letter notation and incorporating the designated theme.
X:1
L:1/8
M:6/8
K:D
['ded =c2 d GFG Add']  
X:1
L:1/8
M:6/8
K:D
 ag |"D" fdd ded |"A" cAB"C" =c2 d |"C" =cAG"G" GFG |"D" Add dag |"D" fdd ded |"A" cAB"C" =c2 d | 
"C" =cAG"G" GFG |"D" Add d2 :: A |"D" dfa afd | dfa a2 f |"C" gag gfg |"A" ecd efg |"D" afd ded | 
"A" cAB"C" =c2 d |"C" =cAG"G" GFG |"D" Add d2 :|  