i have my future plan for my kids,i want to buy bitcoins.In future bitcoin value will rise surely.
Who know about Future? anything can happen hehe, maybe bitcoin get drop to 1K usd then what will you do?
You can't depend only on Bitcoin you should save fiat money for your Kids.

Good advise, investing your kids future in bitcoin is very risky therefore you have to consider some kind of investment as well, we need to learn how to diversify our investing to reduce the risk. Just like anyone of us here, I have high hopes with bitcoin as well but I cannot fully risk what I have since anything can happen and it might not be based on what we are expecting, at least we must be open minded.