Q: Brake line leaking

Brake lines can not be repaired. Replacing the entire line is the only safe repair. After one line starts to leak, all the others will need to be closely inspected. If it is a rear line, the two lines for the rear wheels are beside each other. The fuel lines are usually very close too. Pre-bent lines from Cadillac may be available, but the most common method is to bend custom ones out of bulk line. Do not drive the car even with a small leak. Even though only one line is leaking, you will lose braking force on two wheels. Consider contacting an expert mechanic, like one from YourMechanic, to inspect your brake system and replace your brake lines for you.