This is from Timatic:
Chile (CL)
Minors:
- Foreign minors up to 18 years old arriving in /departing
from Chile and travelling:
- alone, must hold notarized authorization from both
parents/legal guardians;
- with one parent/legal guardian, must hold notarized
authorization from absent parent.
Adopted minors must hold legal permission from the both
Parents (Tribunal Permission/court order).
Based on the above, my next question would be
--does the notarized "foreign" authorization document need to be "legalized" at the nearest Chilean consulate?