It's the evil of subjectivism. Internal wants and desires are deliberately substituted in for reality. They do not believe in "the truth"; they believe in "Their Truth". This was a son because they wanted it to be. The less fortunate children are "fetuses" because they don't want them to be sons and daughters. They feel no cognitive dissonance because to them it is perfectly ideologically consistent. In both cases what they wish to be real is treated as real.

In a sane world, this philosophy would immediately be recognized as insane. We used to lock people up for insisting that what they personally believed dictated reality, but now we charge teenagers thousands of dollars to learn it in college.