I may be who you are looking for. I was adopted in '82 or '83 with my brother (package deal) here in Tx. Our biological parents names were Cheryl and Glen Routon. I was born in 80, my brother in 79.
Growing up, we maintained relationships with an older brother who was also adopted. He was born in 78 or 77. (I know where he is)
I believe we have an older brother (assuming its glen jr) because we were told by our adoptive parents that an older brother was adopted by family.
I hope this helps because there are too many coincidences.
Please feel free to message me