from my AmSlang dictionary

[vriad_lee]

Ahn-paak-ah-tah-nah-kee-woo-zhi-nehr
A male child who is the middle child in a family of three children. The child is usually eccentric but intelligent.
Robert was an ahnpakatanakiwuzhiner. His older brother and younger sister were not as smart as he was.

Comments

[vriad-lee.livejournal.com]

by the way! i'm sure there is some word for your case too, yet another name i could call you. PITA