Plexee is Plex's baby niece. She appears in "Baby" and "Day Camp." She is voiced by Penelope Jacobs. She is 2 years old, as mentioned in the episode "Baby". She was born on May 20, 2007.
Plexee looks very similar to Plex, having the same bright yellow, cylindrical body with blocky yellow hands and feet. She has the same shiny metallic arms and legs, but they are pink. She also has three black antennas on her head, two on either side and one on top, which is topped with a pink bow. Her screen looks almost identical to Plex, the only difference is that she has small eyelashes.
Plexee was retconned out of existence in the Yo Gabba GabbaLand! episode “Make”, where Plex gives a brief speech saying that he doesn’t have any family members.