At the conclusion to the last issue Boston Brand was asked to try and bring back Dove’s sister Holly, the Hawk who died during Blackest Night. Since Dove (Don, not Dawn) was at peace and wouldn’t rise, and Holly was right there, they go for it.
Boston’s ring doesn’t seem to work at first, but Dove tells him to try thinking about the things he enjoyed when he was alive, as not being a Green Lantern means willpower probably won’t do anything.
The ring says “He loved cheese-burgers.”
And then Black Lantern Hawk (Holly) rips out of the ground and attacks him demanding his ring and to be taken to the Lantern. A construct Dove (Don) comes from his ring as the ring says “Despite what others have said”, and then Black Lantern Hawk vanishes along with it as the ring says “Dead isn’t dead.”
The grave is not disturbed, but all three of them saw everything that happened. The ring calls it “A warning”.