Rukelion hadn't known what to say to his children about his home when they were little so he chose to say nothing at all. He figured it would be better until they were old enough to keep secrets so he decided not to tell them anything until they were old enough to learn fire magic.
Having that to look forward to with Roselia filled him with anticipation so great it managed to lessen his anxiety in the few months before her seventh birthday. He was ecstatic at the thought of finally being able to share his heritage with someone who would get it. Daisy was a wonderful listener but she wasn't a fire mage so it wasn't the same.
Years ago, after Peony was born, they had gotten into the habit of having daddy/daughter and mommy/daughter dates where one parent took Roselia out to do something fun just the two of them and the other stayed with the baby since bringing her places could make things difficult sometimes.