Firstly, there is no doubt that the look can cause harm to a person. The Messenger of Allah (sallallaahu alaihi wa sallam) said: "The (evil)-eye is true" as narrated in Sahih al-Bukhari. Secondly, the evil eye is in reality related to the unseen soul of a person. When it looks upon something or is told about something, if jealousy is found in him, this creates a special condition in the soul which affects the person looked upon adversely. People who have this power, essentialy have a perverted and lowly soul. Thus, if a mother or wife is impious and lacks the fear of Allah taala and has no relationship to the Deen, such that she does not pray or read the Holy Qur'an, it is very possible that she afflict her own child or spouse using the evil-eye. To protect oneself and one's children from the poisoness eye, one should read the last two Quls and blow on one's hands and then wipe the hands over oneself. It is also permitted to wear a Ta`weez, written by a pious person with verses of the Holy Qur'an, this is especially suitable for very young children and babies. Imam Ibn al-Qayyim r.a. has written at length on this subject in his book: "Zad al-Ma`ad," vol.4 pp.125-138. In this book, the Imam mentions the following true story: "Abu Abdullah al-Saaji was on one of his journeys for the Hajj or Jihad, riding upon his camel called Farihah. Amongst his companions was a man who had a posioness eye, he would never look at a thing except that he destroyed it! Someone said to Abdullah protect your camel from that man he has a severe eye. Abdullah replied: "There is no way he can get to my camel." However, someone informed the man about what Abdullah said, and so he waited for when Abdullah was not there, then he went to his camel and looked at it. The camel began to tremble and collapsed on to the ground. When Abdullah came back he was told that the man had looked upon it, and the camel is now in the state you see it. Abdullah said: "Take me to this man." He was taken to him and stood over him and recited the following words: "Bismillahi Habsun Haabisin wa Hajarun Yaabisin wa Shihaabun Qaabisin Radadtu `Ayn al-Aain alayhi wa `ala ahabban-Naasi ilayhi (then he recited the verse:) FARJI-ILBASARA HAL TARAA MIN FUTOOR THUMMARJI-ILBASARA KARRATAYNI YANQALIB ILAYKAL-BASARU KHAASIAN WA HUWA HASEER." As he said this, both eyes of the man came out and at the same time the camel stood up fine (Ibid, p.138).