My daughter didn’t walk till 19 months old. Shuffled at great speed on her bottom, wore out the seats of her little dungarees. I was concerned when her peers were running round at a year old, felt a bit ashamed, how idiotic of me!
She walked in her own good time, had forgotten all this until I read this thread.
I think it's regional differences...



Then she developed eight more in just a few weeks and had the full set by the time she was just over two years old! They caused her almost no problems, either.