I was taught that a convert loses his relations after conversion:
"גר שהתגייר כתינוק שנולד".
First, after Tzipora allegedly converted Yitro is no longer her father in relation to anything Halachic, and therefore not Moses's in-law. After the second round of Yitro's conversion he "lost it once more".
However, in Parshas Yitro, he is continuously referred by the Torah and the interpreters as Moses's in-law. Moses is also showing a great deal of respect, because of him being his relative - and not because of הכרת הטוב only.
How these interpretations can be explained in contrary to the accepted Halachah?