YES, you should have up to one year at least to have the District Attorney file a complaint. In California, there is a 3-year statute on felonies, one year on misdemeanors. Check your local state's statutes on this.
The sooner you call the police in your jurisdiction, the better; however, remember the police need to take the report, then the DA reads it and DECIDES WHETHER TO FILE OR NOT. A significant delay can cause various problems for the DA's proof. A criminal protective order (like a restraining order) might also be issued in the criminal case.
You may want to get a civil restraining order against the friend's son-in-law, too. The DA's Victim/Witness office should be able to advise you.
Call the police and report the event. The police will take your report and investigate. The police may have the power to issue an EPO (emergency protective order). They will file the report with the District Attorney in your jurisdiction. The filing deputy will review the police reports and will make a determination if there is sufficient evidence that a crime was committed that the individual named committed it.
Are there visible injuries? As part of the package, the police will send over is the DOJ rap sheet on the suspect. Are there any prior arrests and/or convicts? If the DA files, it may be either a felony if the conduct was serious (based on the nature of the injury and the means use to inflict the injury) or a misdemeanor (less serious conduct).
The defendant will be informed that a case has been filed either by the police serving an arrest warrant or by mail that a court date for arraignment has been set. The court will most likely issue a COP (criminal protective order) at the arraignment. These orders are anything from a “be nice” order to a complete stay-away order. A protective order will not protect you; it only gives the police certain power to act if the person comes around. What I mean is a protective order is not going to stop a bullet or end an attack. It’s just a piece of paper. If the person is dangerous you should take steps necessary to protect yourself.
Step One: make the report. If you sit on this, you will only encourage this knucklehead. Step Two depends on what happens in Step One. A civil restraining order is pretty much the same as a criminal protect order; there are subtle differences at this level, but they not important in this discussion.
However, waiting will adversely affect the weight of your complaint. Normally, the police are called contemporaneously. Something like this: “OMG call 911, he’s killing him.” Now, two and half weeks later, people are going to think about why you waited. It must not have been very bad (important, serious, etc.) if the feelings of the old people outweigh your personal safety. Just saying. And, just why did this son in law choke you out of the blue? Just asking. This is the problem when people sit on things. Are you covering for yourself or is this knucklehead a psychotic?
In New Jersey, the limitations are 1 year for a DP (simple assault-harassment) and 5 years for a felony (aggravated assault).
You cannot file for a domestic violence temporary restraining order unless you can establish the required relationship (household member; see 2C:25-19).
You can report the events as a continuing course of conduct on a harassment or threat-type charge. I would report the previous event and the present situation. Good Luck.