The user supplied only X links, and all three direct fetch attempts failed, so the underlying source content could not be inspected. I then attempted multiple corroboration searches using the claim text itself. Those searches found context that early April 2025 saw a sharp S&P 500 decline, which makes a subsequent rebound plausible, but I did not obtain a validated source confirming the exact statement that the S&P 500 recorded its longest winning streak since October 2025, rose 8% from its March 30 low, and added about $4.5 trillion in market capitalization over eight trading days. Because no fetched source in this run substantiated those exact figures, the claim cannot be rated confidently as true or false.