What is the ruling on a father committing adultery with his daughter and conceiving a child with her? And is the child considered a son or a grandson?

The father committed the abomination of incest (zina with his maharim), which is a grave sin and goes against sound human nature. The ruler (wali al-amr) must carry out the punishment of stoning him to death. If the daughter was compliant, then if she was married, she must be stoned, and if she was a virgin, she must be lashed one hundred times. As for the son resulting from this zina, he is an illegitimate son (ibn zina) and is not attributed to the father.