How can one convince parents of the permissibility of slaughtering for charity (sadaqah), despite their fear of envy and their desire to conceal the reason for the charity, or is it better to give money secretly?

The evil eye is real, but a Muslim should not surrender to the whispers of fear of envy and the evil eye to the point that it paralyzes him. One who consistently recites the morning and evening remembrances, such as: "In the Name of Allah, with Whose Name nothing on earth or in the heavens can cause harm, and He is the All-Hearing, the All-Knowing" three times, and recites the two Surahs of refuge (Al-Falaq and An-Nas) and "Qul Huwa Allahu Ahad" (Surah Al-Ikhlas) three times in the morning and evening, will be free from these delusions. Secret charity is better and further removed from ostentation, the evil eye, and envy, because secret charity holds a great status with Allah Almighty.