President Joe Biden will leave a letter for President-elect Donald Trump before leaving the Oval Office for the final time on Monday as part of tradition among outgoing presidents, according to a report.

Every president since Ronald Reagan has left a note for his successor, and President Joe Biden could be the first to write a letter to someone who is both his successor and the predecessor who left a note for him.

Biden conveyed his deep appreciation for first lady Jill Biden, who joined him in the Oval Office. “My deepest appreciation to our amazing first lady with me in the Oval today, for our entire family, you’re the love of my life and the lives of my love,” he said. “My eternal thanks to you, the American people.”