There is no one "most popular" mother-son wedding dance song, as there are many options to choose from depending on personal preference and the style of the wedding. Some popular choices include "My Wish" by Rascal Flatts, "A Song for Mama" by Boyz II Men, "Home" by Edward Sharpe and the Magnetic Zeros, and "Mother Like Mine" by The Band Perry. Ultimately, the best song for a mother-son dance is one that feels meaningful and special to the individuals involved.