> It was completely anonymous, of course, but lately I've been wondering what's going to happen if (let's be honest, when) my children decide to use a service like 23AndMe.
There are youtube videos of people using DNA sites to find their real parents ( some accidentally and some intentionally ). It's pretty interesting if you have the time.
> Will they want to get in touch with the donor or her family?
Human beings are curious creatures. They will initially feel conflicted but the desire to know will prove irresistible. Perhaps to find half-siblings, to help build a family tree for their own kids one day and of course for family/genetic disease information.
There was a woman whose mother refused to tell her who her father was ( either because she didn't know herself or she hated the guy ). So she did a DNA test and matched a distant cousin and they talked and using the woman's age/birth location/etc, the distant cousin was able to tell her who her father was.
> If one side wants to connect, it's probably going to happen.
At this point, it's guaranteed. All it takes is just one person in your family ( parents, siblings, cousins ) to do a DNA test to narrow it down from billions to dozens. It's almost a statistical certainty that someone with direct genetic ties to you has sent their data in.
If your mother told you today that you were adopted, what's the first thing you'd want to do after recovering from the shock?