Anne
In all honesty, if it were Annie or Danielle in the same spot, I wouldn't be happy, but all I'd give is a lecture and a bit of sex education. Teenagers shag people. They will likely whether their parents want it to happen or not. Neither Dean nor I is the type who has the energy to be overprotective. However, Alexandra is neither Annorah nor Danielle. Nor Robbie, for that matter.
Dean can do what he likes, though if he comes home injured I'll be angry. Mostly at him.