Family member and drug use

Tell their parents.

Report to social services if kids are around this and the care levels are dropping.

Report to kids school about impact on kids.

Either do it or don't. The reality is there's no easy way to have this conversation.

There isn't any clever way to front this and there is absolutely no way to ensure they listen or change anything.

Ultimately, you know them and how they behave. You are seeing things that worry you for the safety of the children (how old?) and you want to step in but not take over responsibilities.

The reason I said tell the parents is about the financial support - it may be financial abuse of the parents, exacerbated by their ill health and vulnerabilities. Equally, if the drug user is their child, I assume they are struggling with the illness as well?

I doubt there’s anything you can do or say that will change anything for that relative.

My concern would be the children…

You don't need proof to tell school you have concerns. If they already have concerns too you may help them to increase their level of concern.

Why not ask the school for advice then? If you are happy for your family member to know you've spoken to school, ask the school if they will be speaking to the parent, if so, you could follow on from that conversation.
If they won't tell you or say it goes straight to social services then either wait till that has happened (if you think the family member would tell you about social services involvement) or also bringing up the effect on children would possibly be a good opener (I don't know anything about drug recovery, only about schools/safeguarding and that only from concerns when my DS who has SEN couldn't explain an injury - but having social workers turn up on your doorstep is an unforgettable moment).

There's no point looking for proof. If the person doesn't want to quit and they think denying they are using will enable them to continue then they'll just lie. And they won't stop just because somebody tells them to.
You need to approach it with concern, rather than judgement. If they don't feel like they can trust you they are less likely to take your help.

How much does the cocaine cost? Could be anything from £10 a day to £300 a day - depends on too many factors but from what you're describing, it is far too much.

Most habitual cocaine users will be taking something else as well - alcohol is a common one.

A problem with cocaine is that the user has no idea what it's cut with - it could be baking soda, sugar, flour or boric acid, paracetamol, or a synthetic opiate with deadly effects (fentanyl or a nitazine derivative) or any number of emerging chemicals.

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You can’t deal with the 2 things separately. Just go and see them and say “I’m worried about your cocaine use”. It doesn’t have to be complicated.

They will deny it even if you have evidence. They won’t stop until they are ready to, and unfortunately there is nothing you can do about it. You can make sure the rest of the family are aware so as not to enable them, and be up front with them and tell them that if they don’t make any efforts to stop you will be reporting them to social services.

You could also signpost them to CGL or other organisations that offer recovery support.

I do have quite a bit of experience with severe addiction yeah.
Obviously if there's neglect then SS should be involved. There's a chance you mentioning that and saying you're concerned about the kids could be the thing that makes them try to change. It's different for everyone.

The scale would be used for them to weigh their drugs. Obviously dealers use them but most regular users do as well so it doesn't necessarily mean they're selling it. But they might be.

The fact they are weighing it points to using a lot . Which is probably why they are short of money . At this rate it is only a matter of time before it affects their work . What would they do if they lost their job? And they could also loose their kids if they are using drugs around them . Never mind loosing their liberty as they could be jailed .
I would point this out to them , that you are now aware of their problem. Ask them are they willing to take measures to address this or you might have to get authority involved because if the kids . It might be a wake up call , it might be ignored , but at least they are on notice now.

An addict won't get clean unless they want to get clean.

To make sure their dealer isn't ripping them off? It happens.

Having had an addict in the family, there's only one way, confront and then deal with the answer and sadly they have to want help, help that often isn't there of you'llfind impossible to give. Issue immediately apparent is neglect of the children, whether intentional or not, along side what happens when they can no longer 'afford' drugs, or their health is impacted by them. No formula for help, how I wish there was and we, as a family, tried A - Z, in the end deteriorating health meant alcohol became the end drug of choice and an early death followed.

To weigh their dose out. Or make sure they are getting the amount they pay for.

If you won’t tell the parents the reality of what is going on, then you can’t accomplish anything.

You can and should report to social services. Being a child living with an addict, even a functional addict, is hell.