There's a knowing glint in Ezra's eyes when Qui-Gon gives that explanation. He knows full well about his dad's penchant for flirting, and the results it tends to have.

"Do I need to start worrying about cleaning the house for visitors?" he asks, somewhat cheekily, without stopping to think that he hasn't ever actually teased Qui-Gon about his flirting before. It's just so easy to respond without thinking at all when the words come so naturally.