Travel Requirements With Non-Argentine Children...

[Frinkiac8]

My wife and son went down without me and it was totally uneventful. She had original birth cert and notarized letter, both of which I had apostilled (it's $5, why not) and she was never asked for either or any documentation other than passport. It is good to have these docs as insurance, but just wanted to share this data point.

 

[anainsh]

My kids are European and I've been travelling in and out of the country with them for many years on my own with their passports. As they get older they travel worldwide on their own and without consent. They weren't born in Argentina so they aren't obliged to have a local document.
As for Argentinean with dual citizenship, we can get in and out of the country with a foreign passport. Note that it's sometimes very difficult to renew an Argentinean passport abroad.