@Kevin ******
now that we sorted out you already GOT your one 60 day visit family extension, that leaves you with ONE long term option. Bank 400K baht in a thai bank account for 2 months before and then apply for a yearly extension based on marriage to a thai.
You might, as in possibly get a letter from a doctor saying you need to be here for the birth of your child and the immigration office COULD issue you an extension based on medical reasons for up to 90 days
BUT
face it you entered thailand Jan 1 and have not done anything to secure a long term extension during the intervening time you were allowed here past your 90 days :O I personally don't care in the least about that BUT the immigration office might take a different approach and ask you why you didn't do something BEFORE now to secure a long term extension?
Good Luck, take care stay safe..