I have a situation where the weekly work week is 40 hours. Overtime was worked (8 hours) but the company said where she was off sick the 8 hours OT was included in the week and would only receive 4 hours overtime - is the right?

Can you provide the dates of the OT, sick day, and the payment periods of the check? The way your question is worded is confusing. (Also - is she in a Union? If so, look at the agreement to see how OT is supposed to be paid out, or call her rep... )