She wears it to bed most nights, takes it off first thing in the morning for a bit of a break for a shower, & during breakfast. Then it goes back on.
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On days that are heavy with after-school activities we need to be sure to get those hours in during the day.
There are days now & then when 18 hours doesn't happen - extra dance rehearsals for example, or a special outing or event, being sick & curled up in bed, or an 8-hour visit to the ER for possible appendicitis (it wasn't the appendix but was still very painful)...
In a few weeks she will go to her back doctor for a series of x-rays to see how she does without the brace on compared to when she is in the brace.
She is hoping to be able to reduce her hours in the brace at that point. A lot. The doctor told her last time he was hopeful she could reduce it enough to wear it "just at night". For her that was not good news - she would rather wear it during the day and not at night! I don't blame her actually...