Like every other investment such as real estate, stocks and other forms of investment we know that you can invest in that kind of things and then you get something like say a Certificate or a Binding Document as a proof that you are part of that investment, now that of bitcoin all you have is just your address, your password, key and seeds as proof of the ownership of the wallet.
BTCSo now if one is considering buying bitcoins and saving for his/her children in the future is there any way to do that with bitcoins apart from having to write down your details somewhere. I'm asking because with that kind of stuff if no one knows your seeds or password no one can get the coins.

I think some corganization are already springing up with cryptocurrency investment. bitcoin is an digital money and all investment and transaction one with it are done online, your login details is your only proof of ownership.
Having a monthly bitcoin savings for your children is not the issue but considering the fact that economy also determine the future of bitcoin in the market, its indeed a geat investment if bitcoin continues on the trend it going but you need to prepare for unforeseen circumstances that could make bitcoin if tomorrow turns otherwise, also you need to consier ther factors such as security of your