We have managed to get through to the airline and we need to send them an e-mail detailing what we are taking. They will forward it to their mdical department who will then send back a confirmation e-mail for us to take with us for the booking clerk.
don't know if you have got this all sorted yet, but I do heaps of travelling with my supplies, and have never had an issue. I travelled before having children too, and honestly, travelling with D supplies is a breeze compared with travelling with children!
I have found that NO-ONE needs to know about your supplies. The more people that know, the more trouble you will cause for yourself.
Have a letter from your dr, but you will probably not need it.
Don't tell the check-in staff, even if they ask if you have sharps.
The only people who might have an issue are the security people, and if you have a letter from your dr (which I have never in 15 years been asked for), you will be fine.
Don't tell the airline, they don't need to know, they will just freak out and make your life miserable for you (or your son!)
Don't order a diabetic meal - they are hideous.
When you go through security, don't mention anything unless asked. I wear a pump, and most times it is not even detected. If it is detected, I just tell them what it is. I also carry syringes, and they have never been questioned.
I know this is your first time travelling (or rather your son's) since being diagnosed, and it is scary, but thousands of diabetics travel everyday, and it really is not a big deal.