Leni

Despite being the second-oldest of the Louds, Leni is quite ditzy and is very forgetful, absent-minded, and not that bright. Various examples of her simple-mindedness are expressed throughout the series. She does not know the rules of the game, Marco Polo. She is shown to be unable to walk and chew bubble gum at the same time. When she's being interviewed she states her favorite color is "zebra."

Her ditzy nature has also caused her to behave like a child, She gets stuck in Lily's crib, calls it a "baby prison," bawls like a baby, and then gratefully says "a-goo" once she gets out; and when she gets a minor injury and refers to it as an "ouchie"

Despite being ditzy and absent-minded, Leni's shown to be skilled at fashion designing, wood carving, singing, lock-picking, and making smoothies, which demonstrates that while she may not be very bright, she is creative and artistically inclined. She is also very friendly and gets along well with her siblings.

Leni is arachnophobic, This phobia is most prominent when Lincoln brings his class's pet spider, Frances, home. When Leni first sees Frances, she panics and attempts to kill her with bug spray. Later on, it is revealed that Frances is still alive, and Lynn Sr. – who is also arachnophobic – had hired an exterminator to dispose of her. Leni faces her fear and cuts off the exterminator, in order to save Lincoln's reputation – once again – showing that she does have a big heart and loves her family.

Leni has also proved that she can be irresponsible, such as when she agreed to cover for Luna, Luan, Lynn, Lucy, Lola, and Lana, but later passed the task onto Lincoln. However, Leni is shown to be very compassionate, as she was the only one of her siblings to prioritize helping her family get better, as opposed to getting away when the Loud family caught the flu. In addition, she is the only person in the family considerate enough in the family to be able to make the perfect surprise party because she pays attention to what people like (excluding the surprise part since she always spoils the surprise because she cannot keep it a secret due to her ditzy and naïve personality).

Sometimes, she is too permissive for her own good. She let a bunch of shoppers take her stuff and was not even upset about it, saying that she would just make some new clothes out of her old ones. Though her siblings taught her to be tougher, she decided that she likes being nice more, as she gave some of the clothes she bought away to people who needed them more. In "Everybody Loves Leni", she worked very hard to bring her work friends and school friends together. She felt guilty for all the arguing between them and punished herself by missing out on her favorite sale, but her friends decided to get along for her sake.

Leni is also very perky and optimistic. When she subbed for Ms. Carmichael in "Leader of the Rack", she wanted to be "fun" despite being the temporary manager, calling herself the "funager". She's also shown to enjoy various playful activities, such as using a trampoline

City, then anywhere else.