Why are lithium salts commonly hydrated and those of the other alkali metal ions usually anhydrous?

(N/A) Lithium is the smallest in size among the alkali metals.
Hence,$Li^{+}$ ion can polarize water molecules more easily than other alkali metals due to its high charge density.
As a result,water molecules get attached to lithium salts as water of crystallization.
Hence,lithium salts such as $LiCl \cdot 3H_{2}O$ are commonly hydrated.
As the size of the ions increases,their polarizing power decreases.
Therefore,other alkali metal ions usually form anhydrous salts.