You'd be better off doing a fasting test in the morning before breakfast or a few tests to see what was going on. If you've got concerns go to your GP but I personally think what you quoted is a non diabetic after meal test. If your child were to show other symptoms like thirst, bed wetting, tiredness, losing weight you might need to look closer.
There isn't that much research on non diabetic bsl's but I test family etc and there is still a fairly broad variation, but no really high stuff. Even my sister after the gym was 3.3 but obviously not a problem in someone without diabetes. My mother hit an 11 after breakfast at the golden arches. She was concerned she might have T2 but after all the tests was told there was nothing wrong. I hang in the 5-8 range all the time whenever I've tested during the day but at a glucose tolerance test while pregnant I had a fasting bsl of 4.1.
All the best and hopefully no symptoms or problems arise.