Larry Koopa has been stated to be the youngest of the Koopalings. He seems to have an interest in sports as seen in many games; oddly, he hasn't appeared in any sports game. Additionally, he doesn't possess a lot of stamina despite his liking of sports. Though he does play tennis with a fireball in Mario & Luigi: Superstar Saga, he has also shown to be bad-tempered or bratty in New Super Mario Bros Wii. His main color representation is sky blue. Larry was known as Cheatsy Koopa in the cartoons, since if he can't win, he will try to cheat by any means to win.
Morton Koopa Jr. is the second youngest of the Koopalings despite his very large size. He seems to possess a cantankerous personality. He is also the only Koopaling to have a different skin tone rather than the yellow tone the others have, this could be because he normally rules a hot and dry area (Desert Land in Super Mario Bros. 3 and Donut Plains in Super Mario World). The Jr. following his name has sparked some controversy; this is due to the specific connection not being confirmed. The actual reason for the "Jr" is because he was named after Morton Downey Jr. His main color representation is black. Morton was known as Big Mouth Koopa Jr. in the cartoons.
Wendy O. Koopa is the third youngest of Koopalings, as well as the only female. She is considered a spoiled brat with a quick temper, often going into a rage over little things. Instead of the spiked bands the other Koopalings have on their wrists and neck, she has a necklace and very large bracelets. Regardless of her feminine traits, as a female villain she is stated to be a tomboy. Even though she is female, she is one of the two Koopalings with no hair (the other being Roy). Wendy was known as Kootie Pie Koopa in the cartoons.
Iggy Koopa is the middle child of the Koopalings. He is depicted as a demented, mechanical genius. His two outstanding characteristics are his glasses and his height; he is shown to be the tallest and thinnest of the Koopalings. The cartoons have also stated that he is the twin brother of Lemmy Koopa (Hip Koopa), but this is not followed in the game canon. His main color representation is yellow-green. Iggy was known as Hop Koopa in the cartoons.
Roy Koopa is the third oldest of the Koopalings. Roy is sometimes depicted as a typical bully who likes beating up others (mostly Iggy and maybe Lemmy) for his own amusement. However, he seems quite fond of the color pink; he has a pink head, pink sunglasses, and a purple shell. This is most likely a reference to the joke, "Real men wear pink." His main color representation is purple. In Japanese materals, Roy is shown to speak in a calm and collected manner, so he may have more of a laidback personality. Roy was known as Bully Koopa in the cartoons.
Lemmy Koopa is the smallest of the Koopalings, despite being the second oldest; he retains a childlike innocence about him. Because of his traits, Lemmy is exceedingly immature; he prefers clowning around rather than conquering. Already being clownish from his love of balancing on his rubber ball, it is stated he would rather join the circus than try to destroy Mario. His main color representation is yellow. Lemmy was known as Hip Koopa in the cartoons.
Ludwig von Koopa has been said to be the oldest Koopaling and was Bowser's second-in-command until Bowser Jr. came along. He possesses a magnificent intelligence, most likely superior to that of his siblings and his father. He is presumptuous, arrogant, and the cruelest of his siblings, but is still very much into culture; he likes listening to classical music and he is a composer himself, as he apparently composes "Koopa Symphonies" (which are said to be terrible). His main color representation is deep blue. Ludwig was known as Kooky von Koopa in the cartoons.