First, I need to parse the search results. The key points from the sources are:
1. Sen. Marshall discussing Biden’s cancer diagnosis timing and potential cover-up (sources 1 and 2).
2. His claims about Biden’s cognitive decline, linking it to Parkinson’s via gait and shoe changes (sources 3, 4, 5).
3. The White House’s response and denial (source 5).
4. The call for transparency and cognitive testing (sources 3, 4, 5).
I need to structure this into 8 paragraphs. Start with Marshall’s main allegations, then specific examples (shoes, gait), mention the cancer diagnosis timing, the White House’s response, the implications of a cover-up, the demand for tests, and conclude with the