https://www.biorxiv.org/content/10.64898/2026.03.11.711219v1...

"Hypothesis: A modern human range expansion ~300,000 years ago explains Neandertal origins", an alternatate take by David Reich, who has done a lot of work in this area. He notes that Neanderthal haplotypes appears largely replaced by Sapiens.

This would make them our siblings rather than our cousins.