"Make sure you have your beeper on,"

I said as I rushed out the front door.
I had to spend yesterday at the showgrounds. I was on duty in the handicraft area again. I needed to be there in time to give someone else a ticket to enter the grounds as well. 
Middle Cat was taking me. She was running late because my BIL was blocking the driveway with the vehicle he was taking interstate. That vehicle was hitched to a heavy trailer loaded with two go-karts and all the other paraphernalia involved in a weekend of racing. No, don't ask!
The person who comes in to help the Senior Cat shower had already arrived so all I did was say, "Make sure you have your beeper on."
Oh yes, he would. The person who sees to his showering said she would too.
Confident that all was well I went off believing that the Senior Cat would be wearing his security pendant or, as he calls it, "beeper".
When I arrived home late yesterday afternoon the Senior Cat said rather hesitantly,
    "Your father is getting dopey."
    "What have you done now?"
    "Well I didn't tell you because I knew you had to go out but I can't find my beeper."
I looked at him - and tried very hard not to get very, very angry.
    "I put it on the handle of the walker when I was getting dressed and I think it fell off in the access cab yesterday. I didn't want to tell you so...."
I went on looking at him.
    "Well I looked everywhere - three times - and I still couldn't find it so I rang the ambulance service and they sent a new one by courier." (The ambulance service is in charge on the security pendant service he uses.)
All right I suppose he had another one within two hours and the courier service they use would have made certain he answered the door and was wearing the new one before they left but....
I would not have left the house if I had known he could not find it. I would have waited until the situation was sorted out.
The Senior Cat hates wearing the pendant. I don't blame him. It's a reminder of all sorts of things he would prefer not to think about. He doesn't like things hanging around his neck - the safest option by far -  and he has set it off accidentally on a couple of occasions. (They answer promptly and he has had to explain he's fine and it was accidental. They seem to be used to those sort of calls! On the two occasions we have needed to call them urgently they have been there promptly and he has been taken to hospital. It's a wonderful service and makes my life much easier too.)
But, he does need to wear it. It is peace of mind for both of us - and it would not have been yesterday if I had known what was going on. 
Next time I see S.... when she comes to help him shower on Monday I am going to ask her to check he is wearing it before she leaves and, if he ever loses it again, to make sure he has called Middle Cat  before she leaves the house. 
Middle Cat will growl much more effectively than I can because she doesn't have to live with him.