I can tell you that by the end of the series,
Spoiler (mouse over to view)
Balsa and Tanda do get together
, but I don't know if they ever
Spoiler (mouse over to view)
have any kids.
By the end of the series, Balsa is in her late 30s, so it's certainly possible. And, the author, Nahoko Uehashi, is still writing material for the series; the most recent book, Traveler of the Wind, came out in 2018; but other than the fact that
Spoiler (mouse over to view)
Balsa and Tanda are together
I can't seem to find much more information about it.
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Self-Appointed Moribito-Series Ambassador to the English-Speaking World