There's no such thing as a normal family, just what you make it.
Adverse childhood experiences (ACE) is everyone's problem not just a select few. It's important to realise that mental health issues, don't just spring up out of the blue. Although they may appear to, most mental health issues are linked to suppressed trauma & adverse childhood experiences.
Hence the next time you're tempted to judge someone for their difficulties, I'd like to encourage you to consider how your response can be contributing to their trauma & enabling their behaviour. xe