Communication is a very important aspect of strategy and tactics.
My suggestion would be to access and learn from this event.
If I may, just real quick-
-Squeaking stairs are a very good early warning system in not only "communicating" someone is stirring, also in "communicating" where.
-Occupants of a structure, be this a house and family, or business and employees, need to have practiced plans and communications.
i.e. codewords, signals, and passwords.
My second wife and I worked various schedules, we also had her son, my stepson in the house.
If I arrived home in the wee hours from travel, there was not only verbal communications, also non verbal.
The dawg of course would greet one of at the door. Now he knew the sound of our vehicles, and the vehicle of the son/stepson's biological dad.
He had a certain way he greeted us.
If he did not know the vehicle, as happened with me a few times driving something else, he gave a early signal of "I do not know who this is"
If he thought it was threat, he would "paw" the door differently than he did when he needed to go outside.
When we entered, we greeted him a certain way, meaning everything was fine.
If, we greeted him another, it sent a signal we had a problem. Maybe one of us were at gun point, and BGs were nigh.
Or
We might get up, for whatever reason. In our master bedroom, we moved our clocks a certain way. All it took was glancing over and seeing where the clock was, to know one of us was out of bed.
A couple of lights were used, day or night, if certain lighting was on, it meant trouble.
I mean in daytime, if anyone of us came home, or came inside from walking the dawg, doing yard work, visiting a neighbor, etc, and saw a light on, that meant BGs were in the house, and practiced plans went into motion.
Verbally...all the time.
We had code words that meant everything was fine, or something was wrong, and some codewords gave more direct information as to what was wrong.
Even if others were asleep, we said these words.
Nobody knew "the codes", except us.
Son/Stepson, did very well with all this.
His dad was a real jerk and his mom divorced him for many reasons, including mental abuse.
The boy felt really safe and good about all this staying safe.
His dad, got a new vehicle, and the dawg went into "I do not know this vehicle" mode.
Of course this dawg hated this jerk, and would communicate "that jerk is here again"
The boy came to the door, used his key to unlock and sat down a backpack, just inside the door.
and greeted the dawg with a pre arranged code, that let his mom know, and me, there was a problem, and with his dad.
Now he had to back to his dad's vehicle for his duffel and other items.
This dad never knew all of this.
He was surprised as heck, we knew there was a problem, and he was the problem.
The boy never told us, he was not yet in the house. His dad never had him out of his sight, and hearing range.
Mom and I come out, and his mom "okay , what did you do this time?"
His dad freaked.
He had been a jerk, and the boy did not "tell us" .
Heck this dad called one night, after midnight, and his mom and I woke up of course and we saw a light on...the one that meant something wrong with the boy.
WE also knew the problem was in his bedroom.
We did this stuff at the old house, when we built a house, some measures were built in, and much more...
This happened in the new house, so his mom got up to see what was wrong.
I knew she was up as one she woke up as I had, and she moved her clock anyway.
Practiced plans.
When she came back to bed, she put the clock back as it was for normal.
There are a lot of very simple, ways to communicate.
Wife and I had guns not only in the bedroom, also elsewhere in the house, garage, shed...etc.
Not once did we ever point a light, or gun at any other member of the family , including the dawg.