Big Brother and Little Brother are twin seamounts rising from 800m of open ocean, approximately 55km east of Al Quseir in the central Red Sea. The two reefs sit 1.5km apart, each with its own structure, its own dive profiles, and its own reason to be on the list.

Big Brother runs roughly 400m north to south, a narrow ridge rarely more than 50m across. The lighthouse at the island's centre was built by the English in 1880 and still operates today. The north plateau sits at 12–18m, the Numidia lies on the northwest face here, cascading from 8m down the wall. Further south along the west wall sits the Aida, resting at a steep angle from around 16m down to 65m. The walls on both sides drop sheer to beyond 100m. Moving south, the ridge opens onto the south plateau at around 18–25m: broader, more exposed, and where the pelagic action concentrates. Oceanic whitetips work the water column here year-round; threshers are a consistent sighting at depth. Currents run predominantly north–south and are strongest around both tips.

Little Brother is smaller, steeper, and more exposed. The reef is roughly oval, rising sharply on all sides with no significant ledge to shelter behind. The north plateau, at 15–22m, is the focal point of almost every dive here. Scalloped hammerheads are sighted in the cooler months, typically one or two passing through rather than the schools that form at Daedalus, but the north plateau is where they appear, early morning before the current builds. From the north, the walls drop sheer on all sides to beyond 100m. The south wall is more exposed and more current-swept, where grey reefs and silkies concentrate in open water. There is no sheltered side on Little Brother, the current dictates where you dive and how you exit.

Both reefs are liveaboard-only. No day boat makes this crossing.