Suppose $\mu \in P(\mathbb{R}^d)$ and for each $n$, $T_n:\mathbb{R^d} \rightarrow \mathbb{R^d}$ is such that $T_n \# \mu$ has a finite second moment. If  $\{T_n \# \mu\}$ converges weakly to $\nu \in P(\mathbb{R}^d)$, could we find $T:\mathbb{R^d} \rightarrow \mathbb{R^d}$ such that $\nu = T_\# \mu$ and $T \# \mu$ also has a finite second moment. This problem is very similar to [Limit of pushforward measures of random variables is "represented" by a random variable][1]. It would be great if any reference book and paper could be given. 


  [1]: https://mathoverflow.net/questions/145190/limit-of-pushforward-measures-of-random-variables-is-represented-by-a-random-v