Family and friends are probably the people who know the survivor best and can help them through this.  As a family member or friend, you may be able to help the survivor feel safe just by being near them.  You may be able to provide emotional support and help the survivor reach out for services.

The most important things you can do to help a survivor heal is to be consistent in letting them know you believe them, that the assault was not their fault, and that you will do whatever you are able to do to support them over time.  It is not always easy to be a helper for survivors, but your efforts will be well worth it.