blood ties

Right, let me start by explaining that I watched the both versions so... I did pay attention -in fact, "Unigamis-2006" is more explicit than the first one.
Still, there are some family connections I don't quite "get".

Methodology: let's trace everybody back to the patriarch shall we?

-First, the official granddaughter announces that she is pregnant from ...her cousin (the 2nd daughter's son)?!

-Secondly, the final revelations make Matsuko's son miss Tamayo's cousin -here, yet again, is some more than a hint of a relationship between these two.

-As she (...), Matsuko urges her son to "make Tamayo not miss her father" (or at least is what the subtitles say, my Japanese being not exactly up to speed!). What does she mean? Who/where is Tamayo's father? Did she mean: a daughter should get on well with her father -or rather, vice-versa: a father should not hate his daughter?

-Why couldn't the patriarch recognise the daughter of "the only woman he loved"? I mean, in his over-dominating position, it's not as if he showed an awful lot of concern for the rest of his concubines (exiling them after they bore him a child)! His "master" must have been dead for quite some time by then.

Any clarification welcome, doomo aligato!