Two of Danaus' fifty daughters (the Danaides) were named Kleopatra (one whose mother was Polyxo the other the daughter of Phoibe or Atlanteia). The two along with their sisters (and half-sisters) were married to sons of King Aigyptos (by his various wives). The night of the wedding, Kleopatra as did all but one of the Daniads killed her husband.
When Kleopatra and the other Danaids who had murdered their husbands they were sent to Tartarus and were forced to carry water from the river Styx in a bowls (or jars according to some) with holes over to a tub which leaks at multiple parts. Kleopatra and the others were told only when they filled the tub could they wash away their sins. The Danaids continue this essentially impossible task to this very day.
Spouse & Lovers
"[The daughters of Danaus married the sons of Aigyptos:] Hippodameia went to Istros, Rhodia to Khalkodon, Kleopatra to Agenor, Asteria to Khaetos, Phylodameia to Diokorystos, Glauke to Alkes, HippoMedusa to Alkmenor, Gorge to hippothous, IphiMedusa to Eukhenor, and Rhode to Hippolytos. These ten sons had an Arabian mother, while the girls were the daughters variously of Atlanteia and Phoibe, two Hamadryas Nymphai." - Pseudo-Apollodorus, Bibliotheca 2. 17 (trans. Aldrich) (Greek mythographer C2nd A.D.)