This frees you from having to assert your productivity while away. If you have something you can point to as a product of your time away, it answers the very basic question of whether this was beneficial/productive time for you and the company.
The people you’re going to be around might not understand that the requirements for productivity during this time are actually higher (see below). Don’t worry. Your in-laws/parents will be impressed by your work ethic!
You don't have to advertise your absence to the entire company, but we do want the people who are looking for you to know where you are. Theoretically, there are standard places we post this, but that's different from making people aware. Make sure your team and the people you work with regularly know where you are.
When you return, check in with your team lead about your time working remotely.
At our company it’s sort of assumed that everyone’s working steadily and diligently. In the absence of new information, the assumption is that you’re producing. When you step outside the HQ work environment, you should flip that burden of proof. The burden is on you to show that you’re being productive. Is that because we don’t trust you? No. It’s because a few normal ways of staying involved (face time, informal chats, lunch) have been removed. You still have stuff like chat, commit messages, code reviews, cases, Trello boards, etc. Be a little paranoid for this time about showing your work. It will help you feel good about your time, and us feel good about granting it.