Doris Day to I Wonder Who's Kissing Her Now in 5 Steps
- Doris Day recorded a duet of "Makin' Whoopee" with Danny Thomas
- Danny Thomas starred in I'll See You in My Dreams as Gus Kahn
- Gus Kahn wrote It Had to Be You
- It Had to Be You was produced by Derek Taylor
- Derek Taylor produced I Wonder Who's Kissing Her Now