Simple random walk on the vertices of a cube

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Here I am considering a simple random walk on the vertices of a cube: at each time, an ant jumps from one vertex to one of its neighbours, each with probably 1/3.

$v_0$ is a fixed vertex of the cube and the chain also starts here. We let $T_{v_0} = min\{n\geq 1 : X_n = v_0\}$ and $\mathbb{E}[T_{v_0} | X_0 = v_i] = m_i $

My goal here is to show:

for $i\neq0$ $$\mathbb{E}[T_{v_0}|X_1=v_i] = m_i + 1 $$

However, I don't know really where to start here. Any assistance would be greatly appreciated. Thanks in advance.