Elizabeth Lauten, communications director to Rep Stephen Fincher, commented on Malia and Sasha Obama's pose and dress at a White House ceremony last week in which the president pardoned a turkey, a presidential tradition for the harvest holiday of Thanksgiving, when Americans partake in a feast that features the turkey as its centerpiece.
She wrote that the girls should have shown more class in both their dress and behavior.
Lauten later apologised for the comments on her Facebook page that had drawn harsh criticism.