Keegan

The meaning here is said to be from a diminutive of Aodh (fire), but that doesn't explain how there's a G in this name, unless -gán is a duminutive suffix as well as -án and -ín. I had guessed the meaning was 'fire-born', with -gán meaning 'born' as in Comhghán. But if I archaify this to Maqas Aidugani (son of Fireborn), the G is medial to vowels, so I would expect the G to have been softened, as in Comhghán. On the other hand, lenition (such as G to Gh) doesn't always work how I expect it to, in my limited knowledge of it. Anyhow, 'son of Fireborn' sounds just as plausible as 'son of Fireling', ImHO.

From the Gaelic language. Keegan (Key-gan); Small, fiery one or Fiery Heart.
My son's name. And he is a Fiery Heart.