Where can I get patent family information? I know there are several paid/subscription tools which can retrieve the information. However, is there a way to get the information using common/free database?
Yes. The Lens is a public good, non-profit and global facility that provides comprehensive family information, including analytics at no cost, and with no advertising, and no compromising of the security and privacy of any user.
It has done so - as Patent Lens - for over 15 years.
Here is an example from one of my patents.
This type of query is available for all ~95M patent documents in the Lens, and results can be collected, annotated, shared and embedded.
Hope you like it.