We usually don't worry about insufficient (or excessive) growth until a child's growth rate has crossed at least two percentile lines (e.g., from above the 90th percentile to below the 50th).

On the T-score scale, 0 represents normal, healthy bone density of a 30-year-old person (the age of peak bone density). T-scores above 0 and slightly below 0 are within the normal range. Your score ...