Yes, yes and yes again, she needs travel insurance! It covers all sorts of things, from flight delays to lost or stolen luggage or belongings aswell as covering her for personal liability and for medical reasons. My brothers step daughter broke her back in Tenerife when she was 20 and after a stay in hospital had to be flown back to the UK, taking up 3 seats (she had to lie down) and accompanied by a nurse. When she landed there was an ambulance waiting to take her to hospital. Can you image how much that would have cost if she'd not had travel insurance?!! You can always try the Post Office travel insurance. You can only get cover up to the age of 74 by going into a branch, but if you ring up they can give you a quote for your Mum
http://www.postoffice.co.uk/single-trip-travel-insurance