I also have orphan children in my lead roles (Zack at least is a true orphan, Kyara's dad just isn't in the picture as far as we know). But instead of having them be completely unsupervised in the "slice of life" portion of CH01, I placed them under the care of Old Nan and her orphanage. From Ch02 onward they are traveling together and there is a noticeable lack of adult supervision though.
That said, the death of Kyara's mother is a big part of her character and plays a major role in the story. So it's not like I dodge the question. With Zack however, I decided it's just not relevant enough to his arc. Maybe one day I'll explore it, but for now he has other issues haha.
I guess that's a weakness I grew out of, accepting that some things just aren't as relevant and cutting them in favor of the more important aspects. I've only got limited time to work on this, and while I could technically make a massive epic, dealing with ALL aspects of the world and characters, I prefer to finish the story in my lifetime (just to say, I'm already in my 6th year working on it, and will likely spend 7-9 years more to reach the end of Ch05)