Sorry to hear. The kit includes a compressed gas (C02) cylinder. Depending on the size of the cylinder, it may or may not be able to be carried on an airplane. This item appears to have a 410g (410ml) which is too large to be accepted as a carry on.
www.faa.gov/about/initiatives/hazmat_safety/more_info/?hazmat=11
Hope that helps. She should be able to purchase a new cylinder though.