__DATA__
child,	Parent,	probability,
M7,	Q,	P,
M7,      M28,     E,
M28,     M6,      E,
M6,      Q,      Pl,
& several hundred lines.....

##</code><code>##

__OUTPUT_1__
M7:  M7<-Q = P
M28: M28<-M6<-Q = Pl.E
M6:  M6<-Q = Pl 

##</code><code>##

__OUTPUT_2__
M7:  M7<-Q = P
M7:  M7<-M28<-M6<-Q = Pl.E.E
M28: M28<-M6<-Q = Pl.E
M6:  M6<-Q = Pl