Buying Insurance for Son and GF

[jasardeax]

Our son has traveled abroad quite a bit, but has never bought travel insurance. 
We would rest easier if he and his GF had at least a basic policy for an upcoming European trip. He would be against buying it for himself, so we wanted to know if we can just buy it in their names, pay for it, and gift it to him without him knowing about it until we told him just before their trip.