What is the average blood pressure for a 7 year old girl?

A bit complicated: It depends on their age and how tall they are. For a 7 year old who is at the 50th percentile for their height (half the kids their age are taller and half are shorter), the 50th percentile for blood pressure is 96/57. A more important question is what is a high blood pressure. For a 7 year old at the 50th % for height, about 109/71 is above 90% for bp. See: http://1.Usa.Gov/tzhane.