Lil DeVille is one of the infamous Nazis known as the Rugrats. She was born in 1807, two minutes before her twin brother Phil DeVille. She was the evilest baby of them all, killing her parents at the age of one just because they were annoying. Having been turned into a baby forever by Vendetta Williams, she is now Bowser's one year old adviser (despite being over 200 years old).
Lil DeVille is a baby genius. At only three months old, she successful constructed her first Rocket Launcher. By the time she was eight months, she had conquered all of Spain. She then gave it back because she was only a baby and wasn't fit to rule. Lil eventually managed to kill her parents, but was then sent to an orphanage.
She and her brother stayed in the orphanage for about seven minutes before Vendetta Williams came in to kidnap them. She could have just adopted them (especially being ruler of the country), but that requires paperwork. She took Phil and Lil back to her layer, and made them babies forever with the rest of the Rugrats.
Lil fought bravely during the War of 1812. Besides the occasional stop for a diaper change, she did not quit until the war was over. She was the one who came up with all the plans that squad leader Tommy Pickles took credit for. She let him take credit because most of the plans FAILED. After the war, Phil got annoying and Lil shot him with a dart. She had to drag him around for two hundred years after that. They now live in Bowser's Castle as advisers.