This is what I meant. There isn't anything concrete that holds an older PhD back. I doubt there will be any age discrimination either on re-applying.
However, if you have a family, a mortgage, a car, and a life outside of school that is time-consuming, getting the PhD will not be a top priority. This makes it difficult to do all the logistical things of getting a PhD too--it's not all about research. You have core classes to complete, many tests and defenses to pass, and conferences to attend. Although it's entirely possible for someone to do this, I cannot imagine it would be easy or good for your studies/other obligations.
However, if you have a family, a mortgage, a car, and a life outside of school that is time-consuming, getting the PhD will not be a top priority. This makes it difficult to do all the logistical things of getting a PhD too--it's not all about research. You have core classes to complete, many tests and defenses to pass, and conferences to attend. Although it's entirely possible for someone to do this, I cannot imagine it would be easy or good for your studies/other obligations.