Child marriage and pederasty in general will be legalized via the "Rights of the Child" --- construed to mean "Every child is a sexual being and has a right o enjoy their sexualioty with a wise, caring older mentor," etc. etc.
Obama pointedly met with people like this when he was in St. Petersburg. Some Russian "Youth Human Rights" group (I can't remember the exact name) which advocates for the sexual "rights" of LGBT minor children.
I see their tactics as fourfold:
- The elimination of basic sexual ethics. This has been long accomplished.
- The creation of autonomous sexual rights for children (which you mentioned). This has been started.
- The normalization of homosexuality. This has been recently accomplished.
- The lowering of the age of consent.
Of course, the ultimate outcome of society's march down this road is the elimination of even consent as a factor.