Develop a musical composition by integrating the alphabetically represented musical pattern and the supplied melodic theme.
X:1
L:1/8
M:2/4
K:D
['Ad f/e/d/c/ dF Ad', 'b^a bB']  
X:1
L:1/8
M:2/4
K:D
|: Ad f/e/d/c/ | dF Ad | cE G>B | AD FG | Ad f/e/d/c/ | dF Ad | cB GE |1{G} ED DB :|2{G} ED Dg |: 
 af d>d | cb b^a | bB c>B | Aa ag | af d>d | cb b^a | bB c>d | ed d2 :|  