Sweet

"Sweet Baby James" is an irresistible karaoke choice. Its simple melodic line makes any voice sound good, and any good voice sound great.
https://www.youtube.com/watch?v=D1gdhG1_yBI
James Taylor wrote this as a lullaby for his baby nephew, James (named for him). To this day, he considers it his best song - which is at least bittersweet, 48 years later.
I am not usually a fan of popular waltzes in live performance because the tempo can get wishy-washy and negate the benefits of 3/4. But although that happens a bit here, the heart in the performance makes up for it.
https://www.youtube.com/watch?v=fnWwnBHnqws