Expandable wellbore junctions

An expandable wellbore junction is formed by first under-reaming a bore. The expandable wellbore junction is then placed in the cavity formed and expanded. The junction has one or more orienting latch profiles. A drifting apparatus is used to ensure that the diameters of the legs of the junction. The apparatus is orientated using the latch profiles and a diverter where necessary. After the expansion the cavity is filled with concrete via a tube inserted through the junction. Thereafter, bores can be drilled in the legs using a whipstock where necessary.