You never know what people are struggling with and, in this woman's case, she had just overcome homelessness and addiction.

Danielle Franzoni is a waitress at Thunder Bay River Restaurant in Alpena. She didn't know the couple that she was serving; she made some small talk with them but nothing too detailed. They didn't know that she's a single mom and a recovering addict who was homeless just a year ago.

Even if they did, they likely would've done the same thing again anyways - the anonymous couple left Danielle a $2,020 tip on a $23 bill. On the receipt, it said, "Happy New Year. 2020 Tip Challenge."

Danielle told NBC News that "I feel like I want to say everything from my heart, but this couple has no idea what they have done for my family."

She plans on using the money to reinstate her drivers' license.