Lilly, LE said, stood at approximately 4 ft tall = 48 inches = 122 cm
The WHO average height for a 6 year 2 month old girl is:
116 > 128 cm
(1st to 99th percentiles):
The average height in Canada for 7, 8, 9 and 10 year old girls are:
7 years 2 months = 122 cm > 134 cm
8 years 2 months = 127 cm > 141 cm
9 years 2 months = 133 cm > 148 cm
10 years 2 months = 140 cm > 154 cm
Lilly's height, at 122 cm, is in the:
90th percentile for a 6 year old
60th percentile for a 7 year old
20th percentile for an 8 year old
5th percentile for a 9 year old
0th percentile for a 10 year old (i.e., her height is not listed for a percentile for this age).
The witness (Ms. Haywood driving nearby) thought the girl she saw walking with the boy was 9 or 10 years old (but one source IIRC said 8 years old, so including all years in the range here between Lilly and a 10 year old average Canadian school girl), that would be a delta (difference) of:
7 year old girl >> 122 - 134 cm = 0 - 4.5 inches taller
8 year old girl >> 127 - 141 cm = 2 - 7.5 inches taller
9 year old girl >> 133 - 148 cm = 4 - 10 inches taller
10 year old girl >> 140 - 154 cm = 7 - 12.5 inches taller
So depending on the eyesight at a distance and/or distance of the witness to the kids she saw walking along the side of the road that morning, and/or if they were wearing boots which may have added a few inches of height, and/or if the sun was shining or not affecting seeing clearly at a distance, and perhaps other factors, IMO, like memory/perspectives potentially shifting over time, it being weeks between the sighting and the witness giving their statement to LE, IIRC:
The older girl looked to the witness to be 2 to 12.5 inches taller -- based on national/world averages -- than Lilly actually was when she disappeared.
IMO, if it was Lilly and Jack who the witness saw that morning, estimating the height of a young girl at some distance walking along and it being within a few inches to a foot of the average ages estimated isn't that big of a discrepancy.
MOO