AITA checking my daughter's new friend's background?

I'm a 39F single dad of 15F daughter who recently made a new friend and has been invited to this friend's house for a sleepover.<br><br>Before accepting the invitation, I spoke with the girl's mother and shared our cell phone numbers. My plan was to drop my daughter off and meet the parents in person.<br><br>On the way there, I did a quick background check on the parents by Googling them using their phone numbers. I didn't want to show up unannounced at the door and make the parents uncomfortable, so I gave them a heads up about my visit beforehand.<br><br>When we arrived, I met the parents and we briefly chatted. However, they seemed uneasy when I shared about doing the background check. They told me they're private people and don't appreciate this invasion of privacy.<br><br>Now they think I'm an asshole for doing this without their consent, and I'm wondering if they're right.