Cassie Warren and Jesse Jones have been busy getting ready for the big day on which they'll finally tie the knot – so in the chaotic midst of planning the wedding, Cassie accidentally wrote the wrong address on a wedding invitation that was meant for her aunt and uncle.

Instead of being sent to the her relative's home in Eugene, Oregon – twenty minutes away from where the couple lives in Portland – it arrived at the home of an older couple.

While the recipients could have simply thrown the letter away, they sent it back to Cassie and Jesse with a note inside.

The note read: "I wish I knew you – this is going to be a blast. Congratulations – go have dinner on me. I've been married for 40 years. It gets better with age."

Enclosed with the returned invitation was a $20 bill.

"I was at first annoyed that Jesse was so worried about opening mail and not focused on the conversation we were in the middle of, but after he opened it and saw the note, I was just grateful and felt so blessed," Cassie told KOIN.

The happy couple ended up using the money to take their friend to dinner before he is deployed on active-duty.

Cassie also made sure to write a thank you note back to the mysterious couple so they know that their gesture was well-received.

"It was just a thank you card," Cassie said. "I thought [they] should know [their] act of kindness was appreciated. Not many people would do that for a stranger."

Click To Share The Sweet Surprise With Your Friends (Photos by Cassie Warren)