Madoka kind of knew Gladio would answer this way. It's just the way he is - ever dependable. It's why she turned to him first with this kind of question. Well, the fact that he's on the same team as her also helps, since it means she doesn't have to ask someone from another team to come with her, but it's also just since it's Gladio. Just his answer alone makes her smile.

"Thank you." The genuine gratitude is so obvious in her voice. Madoka makes absolutely no movement to try and pull her hand out of his. "But.. you shouldn't say you're a poor substitute, mister Gladio. It's true that no one can replace someone else, but.. you're amazing in your own way!"

Even if he isn't her dad like Ignis was or like Tony is. Being around him is still comfortable enough that she feels close to Gladio anyway.