On a GoFundMe page, she says: ''Hi, I’m Bethan. This fundraiser is in aid of my brother who was left for dead whilst holidaying in Spain.
''Steen is a strong and determined man and this incident showcases that. A gang of local men chased my brother and after brutally attacking him, they threw him off a cliff.
''It is only through sheer determination and courage that my brother despite his life-threatening injuries managed to get up and walk for help. Had he not done that, the outcome could have been tragically different.
''These men attempted to kill my brother and now we need your help. Steen has two broken arms, one of which is a compound fracture, a broken jaw, a fractured eye socket and skull, a shattered cheekbone, internal injuries and more.
''He needs several surgeries all of which are covered through his GHIC card thankfully. However, there are other expenses that we need help with.
''Steen cannot fly home due to his injuries and won’t be able to fly for over a year (low flying not an option either).
''It is an 18 + hour journey that is expected to be done in a car. We need to raise funds to be able to find suitable travel with medical assistance. Not only that but Steen needs help and support from his family who will need to be with him.
''Meaning travel expenses are soon going to mount up. Whether you help with a penny or a pound, every little helps. Or even a share of this fundraiser. Our family appreciates it all.
''Anyone that knows my brother knows his strong character, I have no doubt he will handle this better than anyone I know. But let’s make it as comfortable as we possibly can. Thank you.
'(We have had our first quote on an estimate of how much an ambulance would cost and have updated the goal accordingly). THANK YOU FROM THE BOTTOM OF OUR HEARTS! ''
She told ITV News West Country: "The biggest concern is the fractured skull and eye socket. They want to operate on that first in Spain.
"He's got a shattered cheekbone, a broken jaw, two broken arms, internal bleeding and he needs to be seen by a neurologist to determine more."
Steen's medical insurance will only cover the cost of medical surgeries, so the family will have to raise the funds for him to be driven back.