We never heard much about Daisy Duck's past in the old cartoons that I can recall.

Here's a scenario I invented for her. Like a lot of girls, I imagine her first job was as a waitress at an eatery. One day, her uniform popped it's buttons as she was waiting on a table. Although not her fault specifically, the manager felt it wouldn't be the best idea for all the customers who saw it happen to see her bringing in their orders.

Initially, I embarrassed Daisy Duck even more, as my first sketch didn't include her undies (my thinking that she got fired because it was a hot day and she didn't bother with her undergarments and that just happened to be the day her buttons gave way). While firing her would've made more sense under those conditions, modesty won out and I drew in some undies for her. Still pretty embarrassing, of course... I'm glad she's a fictional character or else she might kill me.