Metrizable Space is not necessarily Second-Countable

Theorem
Let $T = \left({S, \tau}\right)$ be a topological space which is metrizable.

Then it is not necessarily the case that $T$ is second-countable.

Proof
Let $T$ be an uncountable discrete space.

From Standard Discrete Metric induces Discrete Topology, $T$ is metrizable.

From Uncountable Discrete Space is not Second-Countable, $T$ is not second-countable.