He smiled with a nod at his daughter when she said she felt reassured. Hopefully that meant he was doing this parenting thing correctly. But then Madoka goes and asks that question and he thinks back to the part about Maru.

Still, there's a soft spot in the iron knight's heart for his second daughter and so Ignis nods. "I'm sure your Dad will be happy for you." Because Ignis would pull Tony out and talk to him again if that's what was needed.