You mentioned several symptoms that can be related to hypothyroidism. Also, her FT4 is only at 45 % of its range, while FT3 is only at 25% of its range. Taken together these are what is needed for many people to feel normal. for further evaluation I'd like to ask her which, if any, of the following symptoms typical of hypothyroidism, she seems to have?
More sensitivity to cold.
Constipation. (needs to use laxative or fiber)
Dry skin. (needs to use skim creme)
Coarse hair and skin.
Muscle aches, tenderness and stiffness.
Menstrual cycles that are heavier than usual or irregular.
Slowed heart rate, also called bradycardia.
From what you have said, why did she have thyroid tests done? Just being in range is an inadequate description. The ranges are too broad, due to the way they are calculated, and everyone can have different levels at which they feel normal. So please post her thyroid test results and reference ranges shown on the lab report. Also, please tell us about any symptoms she has.