And... that is a paticular blood line is holy.
I think the "right to rule" has nothing to do with the line of blood.
This kind of thinking is in line with "Tribal" attitude.
As too if Jesus did have children or not... I do not think that the absence of the information in the bible speaks to He did not. Absence of proof does not negate the solid proof it didn't exist.
I'd say IMHO ... that it is very plausable that Jesus did have children. I'd say it is highly likely.