If you take any set of size $\kappa$, $X$, that none of its elements are singletons, then $\\{\\{x\\}\mid x\in X\\}$ is such set. For example, take $X=\kappa\setminus\\{1\\}$.
If you take any set of size $\kappa$, $X$, that none of its elements are singletons, then $\\{\\{x\\}\mid x\in X\\}$ is such set. For example, take $X=\kappa\setminus\\{1\\}$.