I am not adopted but I lost both my parents by the time I was 43 as did my husband. It's a hard thing to be the next living generation so young.
I appreciate your candour about your two sets of parents. I am an adoptive parent and some of my kids have connected with their birth parents; we encouraged it as soon as it was possible. With our first adoptions some decades ago openness was not so common. Now it is and also as you say there is the Internet.
One thing that was hard was raising kids with no grandparents. Some of my kids never met any of them. I miss my mum and dad to this day.