Thank you appleblossom
I understand it was a one-off decision and that is why we settled in the USA and our lives are rooted here. I work for a company here, my son goes to school here, we have a house, we have a car, we pay taxes, we have bills etc. all that stuff. So even though it was a one-off decision, we will never leave the country for more than 2 months, let alone 6 months as we live here now and I'd like to believe that we proved that we now live here on a permanent basis but maybe not so much in the eyes of the CBP/DHS as per the comments here.
The 2 month trip is supposed to be a combination of business trips in other countries in Europe and also some visits to our families.