You are braver than me then. It sounds like your son has a lot of determination.
T1 unfortunately DOES stop you doing everything normal children do. You only need to read what parents of t1 young children have to say. I've lived through it myself although I wasn't as young.
Children diagnosed before the age of 4 often suffer low level brain damage because of hypos and how they affect the developing brain. Once older the brain is less susceptible apparantly. They are more likely to have no hypo awareness. Their growth can be affected by high blood sugars. They are so variable in what they do and eat each day that managing and semblance of control must be a nightmare. This is why I would stick as closely as I could to a routine to try and prevent the dangerous lows and highs.
I was diagnosed aged 18 months and have lived as normal a life as any of my peers, because my parents decided that this is what they were going to try and do. This isn't to say that I didn't have random highs and lows or perfect control, but ti was good enough and I had a fantastic experience because of it. Maybe I do have low level brain damage because of some serious hypos when I was younger, I did however had relatively good hypo awareness from age 3 up (or general awareness if I felt ill or not). I'm not particularly short so I highly doubt my highs affected my growth. The only reason I am so comfortable with my diabetes and have generally been (bar a few teenage rebellion years) is that my parents made it as normal as possible. I was exactly the same as my siblings and peers, apart from occasional injections. I was never stopped from going abroad - we just made sure we carried spares and had snacks in case something happened. I was allowed on overnight school trips and this gave me responsibility for making sure I was fine. This is just not true that T1 stops you from doing everything normal children do. It's a choice and not one that you have had to make yet because your daughter is fine! Be glad she is healthy now!
With everything you can read into the statistics and scare yourself but realistically why live with that cloud over your head. I echo what everyone else has been saying about seeking help, it sounds as if your own concerns about diabetes are being projected onto your child, which isn't an ideal situation.
But maybe my opinion is wrong cause I've probably got brain damage...