My (Now 8 year old) daughter has been pulled out twice for "random" screening. I could tell by the reaction of the TSA agents that they thought this was ludicrous, but they went ahead and made her stand to the side, arms out, while they passed the wand over her. She was 7 at the time..once at DFW, another at San Diego.
As sad as that is, this is the world we live in today. The next mother-murderer-bomber could be a recent convert who doesn't fit the profile and will gladly sent her child to Allah.