The Prophet ﷺ said: If anyone has a female child, and does not bury her alive, or slight her, or prefer his children (i.e. the male ones) to her, Allah will bring him into Paradise. Uthman did not mention "male children".
قَالَ رَسُولُ اللَّهِ ﷺ مَنْ كَانَتْ لَهُ أُنْثَى فَلَمْ يَئِدْهَا وَلَمْ يُهِنْهَا وَلَمْ يُؤْثِرْ وَلَدَهُ عَلَيْهَا قَالَ يَعْنِي الذُّكُورَ أَدْخَلَهُ اللَّهُ الْجَنَّةَ وَلَمْ يَذْكُرْ عُثْمَانُ يَعْنِي الذُّكُورَ