Since the investment is considerable, why choose a loan? If you don't have extra funds, I suggest not to take a loan, but to invest according to your own personal ability. In addition, although altcoins are sometimes profitable, they are also risky. If it were me, I would not choose to use my family's money to gamble, I would try my best.
There's always greed seeing the market on a red charts before and if did loan some funds, for sure he already make profit right now as the market recovers.
If you are going to loan for investment purposes or for trading and you know that you can get that money back in time, then there's nothing wrong about it just don't ask for a loan that you can't afford to pay especially if you lose that money in trading. There's always a risk, but if you personally see an opportunity to buy at a cheaper price, then I think its worth the risk.