- For size or age:
Littler ("That tree is little, but the tree next to it is even littler."). Littlest ("Theo is the littlest of my three little brothers.")
- For amount:
less (e.g. "I have little money. Certainly less money than him.") Least (—e.g. "I have little money, but Jim is the one who has least money out of all of us.")
- For degree or intensity
Lesser (—e.g. "She has little love for him. Certainly, her love for him is lesser than her love for her mother.")
Then what's the superlative form of the adjective "little" for degree or intensity?