Numerous reasons smoking is bad for teens, fucking up or reducing brain development for the rest of their lives.

https://www.cdc.gov/tobacco/basic_information/e-cigarettes/Quick-Facts-on-the-Risks-of-E-cigarettes-for-Kids-Teens-and-Young-Adults.html

Using nicotine in adolescence can harm the parts of the brain that control attention, learning, mood, and impulse control. Each time a new memory is created or a new skill is learned, stronger connections – or synapses – are built between brain cells. Young people's brains build synapses faster than adult brains.

The parents wil lose their lawsuit because of insufficient evidence (merely the kid's testimony) and arguments about the standard form of search.