Thank you i checked an hour after dinner and it was 9.9 and 8.5 two hours after will keep an eye on themEDIT : Totally misread your post. Sorry!
I'd keep an eye on it and maybe take her to see her GP if you see multiple readings like that
8.5 and below I believe is the range for post prandial readings. Yes do a few more readings. If she has two sisters with Type 1 then it runs in the family. Good luck,