I wish ~、「〜できるといいけれど(できない)」という意味です。
family 家族
bring back to、戻す
I wish I can bring them back to their family.
彼らを彼らの家族の元へ返してあげたい
I wish I could help them meeting their family.
彼らが家族と会えるように手助けしたい
If only there was a way to reunite them with their families
Bringing these families back together is something I would like to do
If only ( できれば )there was a way( 方法がある) to reunite them ( 彼らを再会させる)with their families( 家族と)
Bringing these families back together( この人を家族の元に 戻せば) is something I would like to do( これがまた とてもやりたいことです)