There are many men and women who suffer from the bad habit of sometimes cursing their children, etc, out of anger and grief. Remember that in the court of Allah Ta’ala there are certain moments of acceptance during which all du’aas are answered. Hence, at times due to foolishness and stupidity, the children are cursed out of anger, and when the effect of that curse comes upon the children and lands them into a calamity, the parents go around crying, not even realizing that they themselves had asked for this calamity through their curse.
Rasulullah (sallallahu ‘alaihi wasallam) has prohibited us from cursing ourselves, our children, wealth, servants, etc, as it is possible that this curse will coincide with a moment of acceptance. One should exercise even more care in the month of Ramadhaan as the entire month is a period in which du‘aas are accepted. It is thus extremely important to avoid cursing in this month. (Fazaail-e-A’amaal [urdu], Fazaail-e-Ramadhaan pg. 22)