With each company it is different but normally you will need to inform your car insurance provider about all of the individuals living in your residence that are licensed. If you do not want certain household members listed on your policy then some insurers allow you to exclude that person.
Most insurance companies require that the non-family member disclose all household members on his/her policy. That person may have the option of excluding you. In other words, choosing to sign a waiver stating that you will not drive the non-family member's covered vehicle(s) in exchange for not having his/her premiums increase.
In the states where CarInsurance.com offers Direct General Insurance Company products online to exclude a person you first include this person on your application in the ‘Resident’ section and simply indicate that you do not wish to include this person on your policy. Choose from the drop down list the reason why.
Now if two families are sharing one residence and have excluded the other family from their policy then generally that other family's driving records would not affect your insurance rates but since insurance guidelines (as well as insurance state laws) differ, you should check with the insurance carrier to find out for certain.