Can i donate a lung to a family member who needs it?

Yes, but: Yes with a large caveat attached. You must be an exact match, and you must be healthy enough to live on one lung and survive thoracic surgery. Not every transplant program will offer live donation as a possibility, so you need to both talk to your own doctor about your health and then undergo a full battery of tests prior to donation.

Yes one lobe & risky: Live lung donation has not achieved much popularity as only one lobe of five is permissable. Thus two donors give one lobe each to the recepient. Early in 2007 live donor, recepient in isreal was not encouraging. However to save a dying child would be ethical. Few centers offer this and rarely done. Lobe translant has smaller pedicle and bood vessels and bronchi thus difficult.

Usually no: The only way that you can donate a part of your lung to a relative is if the donor(you) are very tall and the recipient is short. Usually the donation is from a parent or adult to a young child. There are situations where you can donate your lungs if you pass away and have a directed donation to a relative, but those are very rare in lung transplantation.