My mum says I was speaking in sentences at a year old, so she was v concerned when DD having said her first word- duck- at 10 months then didn't say another thing until she was almost 2. By the time the 4th one came along & didn't speak until he was almost 3- then immediately in full sentences- she'd given up worrying!
DD learned to read early, but she would have been 4- not 2! They do learn to memorise books at about 3 & appear to be reading, turning the pages at the right time.
All children are different. As long as they can speak adequately when they go to school, what does it matter? Once they are 7 there is no difference at all between children who walked early/late, talked early/late or anything else.
Twiglett, ignore your sister!