Mavone Cousin Contradiction (Warmage)

In Warmage, the narrator introduces the three Gilmoran warmagi and is explicit about which of them share blood:

Contrary to popular belief, though they looked similar, the Gilmorans weren't brothers. Only he and Astyral were related – distant cousins. They just liked to work together and shared similar tastes.Narrator, Warmage

This passage names Curmor and Astyral as the only related pair, implying Mavone has no family tie to either. However, later in the same book, Mavone steps in to soften an awkward remark by Curmor and identifies him as a relation:

“What my cousin means, milady,” Mavone said with his accustomed smoothness, “is that due to the current war effort, such things are precious. They should be reserved for competent warmagi.”Mavone, Warmage

A third data point appears in Thaumaturge, where the exchange below identifies Astyral — not Curmor — as Mavone's cousin:

“Not to mention charming,” Mavone teased his cousin. “My great humility precludes me from mentioning it,” Astyral said, with dry sarcasm.Mavone & Astyral, Thaumaturge

The three passages cannot all be correct simultaneously. The most likely reading is that the Warmage ch.1719 use of “my cousin” was an authorial slip — Mavone was covering for Curmor socially, and the word was applied loosely or in error. The Thaumaturge exchange is the clearest character-attributed instance and points to Astyral.