I spoke with Ed stark a while back on this and what he said was that a parent
with a higher bloodline can transfer that bloodline and raise his child's
bloodline to his level. "example Aeric Bouruine has a bloodline of Anduiras,
Major , 60 his son Alaric has a bloodline of 47, when Alaric becomes regent
his father invests him with his bloodline making Alaric's bloodline 60.