It’s typical for LE to keep details about the investigation from family members. Not only are they concerned about leaks they don’t want families to go vigilante and seek their own justice. It may be hard to believe family members would “leak” information. Most probably don’t mean to but it’s natural that in their distressed state they’ll share info w/a close friend and confidant. That person may tell a spouse/close friend and eventually it gets out. Or the family member is told someone they know is under suspicion and begin acting differently towards them. IMO When it comes to active investigations LE is making the right call withholding all but the most general updates to family. As hard as it is for the family to not know, it’s the best path to eventual capture and successful conviction.