Develop a musical composition by integrating the alphabetically represented musical pattern and the supplied melodic theme.
X:1
L:1/8
M:6/8
K:G
['G3 GBd edB', 'efg edB AGA AGF G2']  
X:1
L:1/8
M:6/8
K:G
|: G3 GBd | edB dBA | G3 GBd | edB AFD | G3 GBd | edB g3 | edB AGA |1 AGF G2 D :|2 BGF G2 B || 
 def g2 g | afd edB | def g3 | afd e3 | def g2 g | afd efg | edB AGA | AGF G2 B | def g2 g | 
 afd edB | def gbg | afd e3 | def gbb | faa efg | edB AGA | AGF G2 D ||  