According to Dion herself, this very nearly happened. The 51-year-old singer appeared on Watch What Happens Live With Andy Cohen on Monday and said she initially wasn't interested in singing the theme song from 1997's Titanic.
"It didn't appeal to me," Dion said of the dramatic tune. "I was probably very tired that day. I don't know, very tired."
Dion said it was her late husband, Rene Angelil, who convinced her to at least record a demo of the song -- which ended up being the actual recording.
"And my husband said, 'Let's hold on,'" she recalled. "He talks to the writer and says, 'Let's try to make a little demo,' and I sang the song once and they built the orchestra around it. I never resang it for the recording, actually. So, the demo is the actual recording but after that I sang it three gazillion times."
When ET spoke to the late James Horner, who composed "My Heart Will Go On," he said he only had Dion in mind for the song. But he said she "loved it" at the time.
"In writing the song there was only one person technically that I felt could sing it, and I've known Celine so long," Horner told ET. "I flew to see her and I played the song for her in a room and she loved it."
"'My Heart Will Go On' has been an important song in my life for nearly two decades," she said at the time. "Now and tonight, I'm very honored to sing it for all of you and for the love of my life. Rene, you will always be in my heart."
Watch the video below to see her moving performance.