85% of Bitcoins are already mined. It means that very few amount of Bitcoins are yet to be mined. So miners will earn less and it surely affects Bitcoin price because supply will not increase, demand will increase for Bitcoin purchase. So market price of Bitcoin will hit to the upward trend.
You don't have to explain it again, bitmover's reply is already understandable.
This is what we expect from bitcoin in 2020, but I think it will still depend on how the investors react on this and if there is more regulations with bitcoin and other coins.
If most of us have been observing the price of Bitcoin we should have an idea when will the investors pull the trigger. It could be in 2020 but on the last two halving we've seen how long it took for the price to increase.
Yes, you will be a millionaire someday. It's better to collect more bitcoin from now on before the price increase higher. You have a big chance to make a lot of money if you have much bitcoin and when that time arrives, you can sell your bitcoin to convert into fiat, and I am sure that you will be the richest person in your family.
There's no need to give him an advice what if he can't afford to buy more than what he has now?