I was talking to Michael about willing assets to family members in the event of death. He mentioned that we should state to whom we are willing the assets in our RRDJ registration.

Is it possible to add my three children as equal beneficiaries? He also noted that they would need to join RRDJ to claim the assets.

Unless you have a will stating otherwise, your children will receive the assets in equal shares. This is the current system, but having a will would provide certainty.

You could file the will with the registry by scanning and sending it to the RRDJ.