What happened was that Aveling's mistress was Marx's daughter, and when both Darwin and Marx were dead, Marx's papers became muddled up with Aveling's papers, and a letter from Darwin saying, "My dear sir, thank you very much but I don't want you to dedicate your book to me," was mistakenly supposed to be addressed to Marx, and that gave rise to this whole myth, which you've probably heard.
Notika tas, ka Eivelinga mīļākā bija Marksa meita, un kad abi, Darvins un Markss bija miruši, Marksa dokumenti tika sajaukti ar Eivelinga dokumentiem un vēstule no Darvina, kurā rakstīts, "Mans dārgais kungs, ļoti pateicos, bet es nevēlos, lai Jūs man veltāt savu grāmatu", tika kļūdaini uzskatīta par adresētu Marksam, un tas deva pamatu visam mītam, kuru jūs iespējams jau esat dzirdējuši.