I have around 25 BTC from back when Bitcoin was around 10$ or lower. At the time, a friend sent them to me and I never thought they would ever be worth much. Since that time, I've moved them around and don't think I still have any original wallet from around that time. I don't have any solid proof of the original transaction (maybe some old Skype chat log). I'm worried that if I tried to cash them out and withdraw to my bank account, I will lose all or worse.
From what I understand, if the government decides to investigate the transaction, they could seize it and put me in jail? The burden of proof is on me right? What's the best/worse case scenario? Any suggestion on how to approach this?
A general answer would be nice but to be specific, I'd be cashing out to either my USA or Canadian bank account.