Create harmonious melodies following the given letter notation and incorporating the designated theme.
X:1
L:1/8
M:2/4
K:C
['c2 Gc d2 Gd _e/d/c/d/', 'cege ce d2 d/e/d/c/ BG']  
X:1
L:1/8
M:2/4
K:C
 c2 Gc | d2 Gd | _e/d/c/d/ _ec | d/_e/d/c/ BG | c2 Gc | d2 Gd | _e/d/c/d/ _ef | g4 :: cege | 
 ce d2 | d/e/d/c/ BG | c/B/c/d/ ec | cege | ce d2 | d/e/d/c/ BG | c4 :|  