I was searching through Ancestry and found a great-great-aunt in an online family tree. So using Ancestry's Message Center, I sent off a message to the owner of the family tree.
I've done this several times and have had interesting conversations with distant cousins, but I knew this cousin wasn't as distant as the others. My initial guess from what I was able to see of the tree was that it was one of two third cousins, who I may have met at a large family reunion in 1990, but otherwise I didn't know anything about beyond their names. I was hopeful of finding another genealogy-obsessed cousin with whom to share research.
The first response indicated they were one generation younger than me, as they referred to my great-great-aunt as a great-great grandmother. But I am 40, and I knew my third cousins could be a few years older than me, so I knew it was possible the person was in their 20s.
A conversation ensued where they responded with 1-2 sentence messages asking me questions, without providing much information about themselves. Most of the responses were during the daytime, which led me astray, as my first thought was they had to be out of high school. But then I noticed the length of the messages were perfect for a cell phone with internet access (though mostly complete sentences without cellphone shorthand), and since I have been away from school-life for about 15 years, it really didn't occur to me that this week was spring break for many schools.
To make a long story short, my cousin is 14, and set up his Ancestry Family Tree 2 years ago. (Perhaps as a school project, perhaps on his own.) On his part, he didn't realize that given names and birth dates of living people are protected information in the family trees, and he assumed I knew.
It didn't take me too long to figure out that something was suspicious, and I didn't say anything I regret, but I may be more direct in the future about asking for basic details. It isn't difficult to set up a family tree on Ancestry, and it's free to do so. So one shouldn't make too many assumptions about those who do.
[It's also something to consider when evaluating the validity of the information in an online tree.]