I just discovered that my brother is vaping (smoking those e-cigarettes with nice-smelling liquids). We are not that close that I can give him advice, as he traveled to study abroad when we were younger and I am much younger than him, but I was wondering whether it would be haram to tell my parents knowing it would greatly disappoint my dad and and break my mother's heart. It might even cause a huge problem ending with my dad and brother not speaking and my brother hating me. Thank you. Please reply ASAP. I am desperate and scared.
All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
May Allah reward you for your compassion towards your brother and your keenness on having his best interest at heart. We advise you, first of all, to supplicate Allah to rid him of this evil and guide him to repentance. Perhaps a sincere supplication from you would be answered and his situation would be rectified, and Allah would give you great reward for it.
Specialists have underlined the great harm of the e-cigarette and that it contains highly toxic substances. They warned that a malfunction in the electronic device may cause acute nicotine poisoning. If this is the case, then the e-cigarette is prohibited and its harm is grave. The Prophet, sallallaahu ‘alayhi wa sallam, said, “Harm may neither be inflicted nor reciprocated (in Islam).” [Ahmad]
Your brother must be warned and given advice regarding using the e-cigarette. You do not have to advise him yourself; rather, you may seek the help of a friend or relative whom you believe that your brother would listen to. If you hope that informing your father of this matter would help realize a benefit greater than the expected harm, then inform him. To avoid putting you in an inconvenient situation, your father can await an opportunity to catch him smoking in order to talk to him or so.
Allah knows best.
You can search for fatwa through many choices