Yes, I think more people need to contact him. Last week, the response to my request was this:
Thank you for contacting me regarding the case of Sean Goldman, who was reportedly taken to Brazil by his mother against the wishes of his father.
My staff has forwarded your concerns to the State Department's Office of Children's Issues, which works specifically on these complex matters. It is critical that these cases are resolved according to international law with the best interests of the child in mind.
I will continue to closely monitor developments on this issue. Thank you, again, for writing.