I want debt collectors to stop calling my family.

If you don't want a debt collector to contact you, the you can give it in writing. If you say so, they can't contact you unless they call you to notify that they won't contact you ever. However, a debt collector can file a lawsuit if the debt is within the SOL period.

No, my dear friend. There will be no violation if you ask them not to call your family.

The FDCPA or Fair Debt Collection Practices Act says you have the right to send a written ‘Cease and Desist’ letter to the debt collectors to ask them not to call you and your family again. Just make sure you have sent the ‘Do not call me’ request through a written letter.

The FDCPA rule says they cannot call you repeatedly in a single day and they cannot call you before 8 am and after 9 pm.

That’s all. Thank you.

Give a written notice and request them not to call ou, Instead contact you via email or letter. They are not liable to call you before 8 am and after 9 pm. Only if they call you repeatedly, you can make a complaint against them

Okay. There are a few things that you can do.

1. Tell them that it's against the FDCPA law to disturb your family time and again. You can file a lawsuit against them for this reason.

2. You can send a Cease and Desist letter to stop all kinds of communication with the collection agency. You can get a sample letter from here.
https://community.debtcc.com/letters/cease-desist.html. But there is one thing that I must tell you. If the debt is valid, then they can sue you. So, before sending a Cease and Desist letter, ask them to validate the debt in writing. Also, check the SOL period in your state. What state are you in by the way?

The collection agency can call your family only once and that too if they can't locate you.

Well, this is one of the common problems people face with debt collectors. As Ryan Miller said that FDCPA gives you the right to ask your debt collectors not to call your and your family repeatedly. You should immediately send a Do not call me request!
Besides, the Telephone Consumer Protection Act (TCPA) prohibits the debt collectors from making unauthorised robocalls to your or your family members. Lastly, don't get scared. Take appropriate step to deal with the situation.