No one has been publicly confirmed as the sender of the skulls to Ethan Klein’s home, and the reports I found say it remains unclear who did it. The available coverage says the package was part of a broader harassment situation, but the sender has not been identified publicly.

What’s known

  • Hila Klein said two human skulls were mailed to the home and that the incident happened around the same time CPS/child welfare issues were being reported.
  • Coverage also says the FBI was involved, but no source identifies a verified sender.
  • Some online speculation has pointed at various people, but that is not the same as a confirmed source.

Most accurate answer

At this point, the safest answer is: unknown. Public reporting has not established who sent them.

TL;DR

The sender of the skulls has not been publicly confirmed.