CMD of the new group. Left: CMD of stars using WFC3/HST data. The red crosses are the new co-moving group sources found in the WFC3/HST data, and the blue triangles are the ones found in our proper motion catalogue. The source with F127M − F153M < 0.5 is a foreground source. The coloured points inside the green ellipse are the new group sources moving in the direction of the Quintuplet cluster movement. Right: CMD of the new group using the GALACTICNUCLEUS data. The co-moving group of stars, excluding the foreground star, is marked in blue. The de-reddened CMD is shown by black points, and an isochrone of 5 Myr old is over-plotted.