Notice it said “family”, not parentS??
Yep, you’re right, the family wouldn’t cooperate.
It’s likely the girls doesn’t live with parents. She may be living in one of those ad hoc “family” arrangements, which are more common among ghetto people than among the rest of us.
And this “family” of hers wants nothing to do with the police.
Heck that right there is half the problem in the ghetto. Too many see the police an an enemy. Combined with the way the gangs intimidate people, it makes for many never solved drive by shootings and other crimes. Nobody will ever testify in court or file reports with police on things they have seen.