I used my family's rainy day fund money to play blackjack at the casino
You did not do that! What did you do instead to spend the money?
I did indeed play blackjack and I won. I was too ashamed to buy nice things for myself, so I invested the money in the stock market.
You're lucky you won, but you shouldn't use your family's money like that. Don't pull that again, because you're likely not going to win the next time.
Ok, I'll put the money back.
That's good that you'll do that.