disbelievers of ignorance era. As they used to bury their daughters alive. Therefore, it is stated in part 14, Surah An-Nahl, Ayah no. 58-59:

وَ اِذَا بُشِّرَ اَحَدُهُمْ بِالْاُنْثٰى ظَلَّ وَجْهُهٗ مُسْوَدًّا وَّ هُوَ كَظِیْمٌۚ(۵۸) یَتَوَارٰى مِنَ الْقَوْمِ مِنْ سُوْٓءِ مَا بُشِّرَ بِهٖؕ-اَیُمْسِكُهٗ عَلٰى هُوْنٍ اَمْ یَدُسُّهٗ فِی التُّرَابِؕ-اَلَا سَآءَ مَا یَحْكُمُوْنَ(۵۹)

Translation from Kanz-ul-Iman: And when one amongst them is given the glad tidings of a daughter, his face darkens for the whole day, and he is full of anger. (He is) hiding from the people because of the shame of this news; will he keep her with disgrace, or bury her alive in the earth? Behold! Very evil is the judgement they apply. (Part 14, Surah An-Nahl, Ayah 58 - 59)

Those who lose their hearts on the birth of daughters or grieve because of this, they should listen to the 4 blessed sayings of the Beloved Rasool صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم in relation to the excellence of a daughter and her birth.

1. When a daughter is born at the house of a person, Allah عَزَّوَجَلَّ sends angels who come and say: اَلسَّلَامُ عَلَيۡكُمۡ اَهۡلَ الۡبَيۡتِ i.e. O people of this home! Peace be upon you. Then the angels take the baby girl under the shade of their wings and, stroking her head, they say that she is a weak being who has been born by a weak being. The one who takes the responsibility of bringing up this weak being, Allah عَزَّوَجَلَّ will help him till the Judgment Day. (Majma-uz-Zawai`d, vol. 8, pp. 285, Hadees 13484)      

2. [If] a daughter is born at the house of a person and he does not distress her and nor does he consider [her] bad and nor does he prefer the son to the daughter, then Allah عَزَّوَجَلَّ will make that person enter Heaven. (Mustadrak, vol. 5, pp. 248, Hadees 7428)

3. One who has three daughters and he treats them well, Heaven becomes Wajib for him. It was humbly asked: If there are two, then? The Holy Rasool صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم replied, ‘Even if there are two.’ It was humbly asked: If there is only one, then? The Holy Rasool صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم said, ‘Even if there is only one.’ (Al-Mu’jam-ul-Awsat, vol. 4, pp. 347, Hadees 6199)