Thuleâs voice, well, I think it must be  something not so far off from Muâs. Velvety soft, eloquently spoken and with resonant low tones, perhaps a bit more than Muâs. Maybe something like Sho Hayami (on his higher range). Â
As for the kids being all spunky, I will say I fear thatâs not the case. I believe it depends on the temper and education of each child. In Kikiâs case, for example, I headcanon his first years he was raised in the countryside before they turned him to Mu for tutelage. His use of the pronoun Oira hints of that. Itâs his admiration for Mu that makes him try to emulate him in a more formal speech and poise as he grows up.  Â
In Muâs case, his character being more mellow,  I believe he picked up Shionâs  Pope-like official and elegant forms of speech from a very young age since I headcanon he was raised inside Sanctuary.
And for the rest of kids in the sheepverse, all of them are different: some very well behaved, some just really energetic, and others that are a complete handful xD Â Â
What is culturally a rule is the respect of life, arts and knowledge, so they all need to have those traits as adults in some way :)Â
