@Annette720
Annette the problem is, the guest is always right....at least that's the way Airbnb see it.
I had the same situation recently, a guest booked for one person but in the booking message said they were a quiet family. I pointed this out to him, he replied that the booking would be for he, his wife, a 10 year old child and an infant. I asked him to amend his guest numbers to reflect the correct number of guests.
The next thing I got a change of reservation request for two adults and an infant. He had obviously seen that the listing fee was for two adults and infants are accommodated at no charge but, the 10 year old would attract an addition $15 per guest fee so he chose to ignore the 10 year old on the booking.
Annette, I knew exactly what was going on, I studied it for a while weighed up the pluses and the minuses and accepted the change request. Sure enough he turned up with his wife and two children neither of whom were infants.
Now I could have refused to accept them and put up with all the hassle that would go with that or just take a hit for that extra $15 per night after all as I have said before 50% of something is better than 100% of nothing!
I gave them a reasonable review and they gave me a good review because, he dodged a bullet!
Once the reviews were posted I messaged the guest and told him he would not want to try and pull that stunt again, other hosts may not be as laid back as I was and he could well find himself refused accommodation for deliberately not declaring guest numbers. I reported him to Airbnb and I don't know what the outcome of that was but from my point of view, Annette, you will get guests that will do things like this, not many but, they are out there. I think you are just going to have weigh up for yourself if is worth having an inquisition over. Personally I wouldn't!
Cheers........Rob