When a booking is received from Booking.com or from a channel manager (in our case Rentals United, I don't know for others), we should get the number of children inserted automatically into Mews. It has impact on bedding and city tax.
As of now we have to go manually in each booking of each platform and manually insert the number into Mews.
This feature is available for all channel managers. In case there is still an issue with Children count, please contact our Customer Care team, so we can investigate on concrete examples.