A manual of Islamic law certified by Al-Azhar as a reliable guide to Sunni orthodoxy says that “retaliation is obligatory against anyone who kills a human being purely intentionally and without right.” However, “not subject to retaliation” is “a father or mother (or their fathers or mothers) for killing their offspring, or offspring’s offspring.” (‘Umdat al-Salik o1.1-2).
In other words, someone who kills his child incurs no legal penalty under Islamic law.
“Man beheads daughter in Rampur district,” from Indian Express, June 20 (thanks to The Religion of Peace):
Lucknow: In a suspected honour killing, a man allegedly beheaded his daughter who was insisting on marrying her lover in Rampur district.
Shaukat Saifi was arrested after he allegedly beheaded his daughter Naseem with a sharp edged weapon yesterday in village Krimcha, about 250 km from here, police said.
While Naseem wanted to marry Yasin, a resident of the same village, her father was opposed to the alliance, they said.