What are the visa extension options for my American kids in Thailand, and what documents do I need?

Hi I am Thai but my kids are Americans. We were awaiting a signature from our landlord who is overseas and was doing her quarantine ... long story short we are a month late to get extensions on a non o 90 day visa for my 7 and 3 yr old. I suppose I could just get a Thai passport for my 3 year old daughter easily but my 7 year old needs a Thai Id and my mother who passed away is the head of the house on my parents’ blue book - so a lot of legal stuff needs to happen until my dad changes everything so he could be head of the house and add my son so my son can get a Thai Id and then a passport and have dual citizenship.

It’s probably a better idea to just keep extending their visas - but which extension should I get (can get if we are renting here and have a contract that ends at the end of the year, and would likely move back at that time)? Also do we go to Muang Tong Tanee and bring just my Thai Id, their birth certificates, passports and our TM30?

Thanks so much in advance!