Answer:
The behaviour that most likely will be least tolerated is her eldest brother behaviour.
This is because her brother is at least sixteenth years old, and he is at an age when juvenile deliquency is very common among certain populations. If he was found by the police vandalzing property as the question said, he would probably be in serious trouble, and could be taken to a juvenile correctional facility. If her brother is even older, to the point of being 18 years old or more, he could be taken directly to jail.
Her younger brother, on the other hand, is fourteen years old or less, and both parents and police would be more lenient with him. He most likely woudn't be taken to a juvenile correctional facility, and jail is obviously out of question.
As for Jane, vandalizing property and committing petty crimes does not seem to be characteristic of her. As she is fifteen years old, parents and police would not necessarily be so lenient with her, however, the consequences for her older brother in the same situation would most likely still be direr.