Q. My son Henry who's 4 is having a flu jab tomorrow, my wife says that we should tell him, I think not, what do you suggest?

Personally I think you should definitely tell him but don't make a fuss. If you don't tell him you run the risk of him not trusting you in the future. All you have to do to avoid potentially having anxiety whenever you leave the house is sit him down and explain very matter of fact what will happen and why. I hate injections and if you do too, you may be assuming he will have a fear. Try to act calmly while he is having it done. If he does show signs of distress just remember the flu jab doesn't hurt - perhaps a sting - but may be necessary for a mere few seconds of discomfort.