Does this exoplanet have a 'sibling' sharing the same orbit?

Using the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers have found the possible "sibling" of a planet orbiting a distant star. The team has detected a cloud of debris that might be sharing this planet's orbit, which they believe could be the building blocks of a new planet or the remnants of one already formed. If confirmed, this discovery would be the strongest evidence yet that two exoplanets can share one orbit.