There are lots of thoughts on this question. It’s tricky, and people tend to be passionate about their opinion. On the one side, you have the camp that would like the authentic accent spelled phonetically every time the character speaks. An example would be the character Jim in Huck Finn. There is a fairly small group advocating this type because this it’s very hard to read. Some dyslexics find it almost impossible, and those of us (like me) who didn’t learn (although were taught) phonetics can’t read it at all.
The next group advocates not using the accent at all. This would be like in the question, where the author mentions the person has an accent, but then never really refers to it again. This method isn’t perfect either since you can lose some of your character’s flavor.
What I personally recommend is the middle ground. This is where you choose some words that are distinctive of your character’s culture, and these are the words you use to highlight your character’s accent. For example, a Spanish child might call her aunt “Tia.” The child might be American in all ways except that she was born in Madrid and moved here in ninth-grade, so she speaks Spanish at home and English with a mild Spanish accent. These little bits of Spanish might drop themselves into her everyday conversation. And this works even if your character’s accent is not derived from a foreign language. Say you wanted to have an older Southern woman. She could call everyone “Dahlin’” while the rest of her dialogue is still spelled correctly.
And finally, there is a lot you can do with word order and word choice. The British speak a comparatively more formal English when speaking Oxbridge style. You can convey a British accent without spelling color “colour.” And people who find English to be a second language often do not have their word order quite right. “I speak the English good, yes?” is a stereotypical sentence, but it illustrates my point.
To see a good example of how to handle an accent in this style, I would recommend looking at any of the Agatha Christie books that feature Hercule Poirot. His English is always spelled perfectly, but there is a distinct French accent to all his dialogue. He occasionally uses French, and at his “most foreign” as she puts it, he chooses to mis-word his sentences. I know this is not a children’s example, but since the character deliberately manipulates his accent in various novels – all without resulting in bizarre spellings, I felt this was the most instructive example.
To see the varying ways other authors have dealt with character accents in children’s literature, look at some of the following:
- Fleur and Viktor in Harry Potter 4
- The various faerie factions in Artemis Fowl all have their own ways of speaking.
- They have southern accents in Roll of Thunder, Hear My Cry.