I just wanted to start with a few ahadeeth which highlight the reality/severity of 'ayn and hassad:
Hadeeth 1:
[ أكثر من يموت من أمتي بعد كتاب الله وقضاؤه وقدره ، بالأنفس ]
الراوي : جابر بن عبد الله
It was narrated that Jabir ibn 'Abdullah said: The Messenger of Allah (Peace and Blessing upon Him) said
:
"Most of those who die of my Ummah, after the will and decree of Allah, will die because of the evil eye."
Hadeeth 2:
{العين حق ، ولو كان شئ سابق القدر ، لسبقته العين ، فإذا استغسلتم فاغسلوا }
[مسلم]
It was narrated that Ibn 'Abbas (RA) said: The Messenger of Allah (Peace and Blessing upon Him) said
"The evil eye is real and if anything were to overtake the divine decree, the evil eye would do so. If you are asked to wash (to treat someone for the effects of the evil eye) then do so." [Muslim]