so if I am day short of my 18th birthday my parents should face the same charges as they would if I were say ten or twelve? Under the law in most states and cases that 17 year old is a child.
You seem to think that because there is an age cutoff that the applicability of the law due to a 1 day disparity makes the law unjust. It's an absurd premise.
You think it's different between age 18 and someone who's 12?
Well, according to you, there's no difference between someone who's 18 years old and someone who's 17 years, 11 months, and 29 days, correct?
Let's extrapolate.
Is there a difference between someone who's 17 years, 11 months, and 29 days and 17 years, 11 months, and 28 days?
Is there a difference between someone who's 17 years, 11 months, and 28 days and 17 years, 11 months, and 27 days?
Is there a difference between someone who's 17 years, 11 months, and 27 days and 17 years, 11 months, and 26 days?
Is there a difference between someone who's 17 years, 11 months, and 26 days and 17 years, 11 months, and 25 days?
Is there a difference between someone who's 17 years, 11 months, and 25 days and 17 years, 11 months, and 24 days?
Is there a difference between someone who's 17 years, 11 months, and 24 days and 17 years, 11 months, and 23 days?
...
Is there a difference between someone who's 13 years, 0 months, and 1 day and 13 years, 0 months, and 0 days?
Is there a difference between someone who's 13 years, 0 months, and 0 days and 12 years, 11 months, and 29 days?
At some point there's going to be a cut off. Unless your argument is that there should never be laws that use age as a measure (drinking age, voting age, age for minor/adult), then there will ALWAYS be a 1-day cutoff between the legality which appears trivial in reality, but is meaningful in law.