While we have the utmost respect for the Brazilian immigration system and for its visa rules, the short answer to this question is, don’t worry too much about it.
Overstaying your tourist visa can happen in two cases:
- You’ve stayed beyond the 90 [or whatever they give you] days initially granted on your arrival card, or the 90 days granted by your extension.
- You’ve stayed in excess of 180 days during your 1 year period.
Once you’ve overstayed your tourist visa you will be subject to a fine of R$8.28 per day that you overstay, with the maximum fine being R$828. Whether you overstay 100 days or 10 years the fine is the same.
The fine will be issued to you when you go to the Policia Federal for your permanent residency appointment. You simply pay the fee, and your immigration status in Brazil reverts to normal again. The fact that you now have a Brazilian child means that the slate is wiped clean straight away.
However, if you overstay your visa and you do not have a claim to permanent residency (i.e. if you aren’t the parent of a Brazilian child or you do not have a Brazilian spouse, etc.) then you are issued with your fine as you leave the country. You do not have to pay the fine until you want to re-enter Brazil next time you travel. Please note, tourists are allowed a maximum stay in Brazil of 180 days in a one-year period, so you need to stay outside of the country for enough time for the clock to reset.