U get 90 days on every entry

Nope

well you know where to go then! Knob head

One warning though if your kid enters on a thai passport and your kids passport expires whilst you are in Thailand and they aren't on a tabiban it will be a pain in arse to leave the country and renew their passports without a thai Id number

Chill man

M8, sorry for being negative, it's not rocket science! My son is a dual national and who will know! Data protection act my friend and the uk allows dual nationality so that won't share data about naionality unless something serious and I've been through thai immigration loads of time with my son and they have seen both passports and no issues