Overstaying visa?

[ndcj]

Do you mean "our" three children or just 'your" three children?

If you are a single parent the fee/fine should be 300 each for each child...as well as the same for you.

If you are traveling without your spouse you will need written permission from her/him to leave the country with the kids.

Steve is right, the fee is the same no matter the age of the passport holder.

You don't, however, need any permission to travel without the other parent with children who are not citizens or residents of Argentina or Mercosur countries. The rule about having notarized permission does not apply in that circumstance.