Emma Willis announced the series' second set of nominations on Big Brother's Bit on the Side.
Between now and Friday, the public will vote to save their favourite of the pair, before the lines close during the eviction show.
Rebeckah and Heaven have irritated Aden Theobald, Jay Mckray and Tom O'Connell in the past few days due to their rift over Rebeckah's claims that Heaven is "bossy".
Last week, Tashie Jackson became the first Big Brother housemate to be evicted in Channel 5's inaugural series.
Big Brother continues on Channel 5 at 10pm tonight.
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Watch Rebeckah and Heaven talk about their falling out below: