@Chen **********
right then the expiration date of the VISA (the sticker from the thai consulate means nothing in the scheme of getting a yearly extension inside the country)
Think of it this way, a visa (the sticker) doesn't let you stay IN thailand, it lets you ask to get in. If they let you in they stamp you in for the length of time that visa allows <- in your case 90 days. It's that small blue rectangular entry stamp that lets you stay here and that expired MONTHS ago putting you on amnesty.
SO as long as you can meet the financial requirements based on marriage BEFORE the 26th of Sept (when this current amnesty expires) you could apply for a year extension based on that. OR as I said, see what your immigration office tells you about the year extension based on having a half thai child, OR get the 60 day visit family extension to give your money time to season.
Those are pretty much your options.