How come people fawn over their baby kids?

and then turn nasty asf to them once they grow up? you know what im saying its true. im not a parent but i dont see any logical reason why one wouldn't uphold this attitude throughout their kids lifetime? so they were "best thing that happened to you" so how come it stops being true as time goes on?

Updates
2 mo
i mean its literally the same person
How come people fawn over their baby kids?
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