HOUSTON -- It is an image that is quickly coming to define Hurricane Harvey.

The picture shows stranded senior citizens -- many suffering from dementia -- in a Dickinson, Texas, nursing home. They were stuck in flood waters up to their waists.

The owners' daughter and son-in-law, Kim and Tim McIntosh, went to Twitter and looked online for a lifeline.

"We were desperate, desperate to get someone there and given we couldn't get through to anybody I felt nobody was listening," Kim told CBS News.

Their tweet went viral, and within a few hours, the residents were rescued.

Among the most vulnerable during Harvey have been the elderly.

Henrietta Belle, 94, was trapped in her house with her daughter and when the water rose 2 feet above her head.

They waited to be rescued with their neighbors.

Read more at CBSNews.com.