Chloe's grandparents, April and Gordon, said they could not understand claims that there were no lifeguards on duty who could have pulled her from the water.
More top news
Isolated afternoon showers are likely over Scotland.
"I definitely get less money than a male in my situation would," she said. "Definitely."
Muscular Dystrophy UK said the lack of an option to label abusive tweets based on disability was preventing more reporting.