Let $X$ be separable Banach space and $\{x_n\}$ be a bounded sequence, relatively weakly compact sequence in $X$. we set $y_n=\frac{1}{n}\sum_{i=1}^{n}{x_i}$, then (together with the Krein and Eberlein-Smulian theorems), we can assume that there exists a subsequence of $\{y_n\}$ converges weakly to some element $y \in X$.

We suppose that every weak limit point of $\{y_n\}$ must equal $y$.

Can we say that $\{y_n\}$ must equal $y$?