Hello @Karo
indeed Mews and Synxis have not created bridges for more than one additional person, this is more on the side of Sabre. On my end, I use 3 child age categories and only one is connected. But to address this, as we know that depending on the ages of the children they have different needs and we need to adjust our rates by increasing them to cover the extra bed, breakfast, etc.
So the solution is in Synxis, you need to create static packages with the different age categories so that when the guest makes a reservation on the booking engine it reflects that of Mews and I must say it works well.
Then, at the reservation level, when we receive the confirmation, we need to adjust the child's age in Mews and the products will be added with the age category.
Unfortunately, there is no bed inventory which is alarming and unfortunate! I urge you to ask the developer or your key account at Mews for this! But not to go vote but to make NOISE.
For any configuration, I recommend @marc agilotel
Best regards