US Immigration from Switzerland

Hi everyone!

My husband and I just got approved last week on our I-130 petition!! and we recieved the email from the nvc that they recieved our case. Now we're a little bit confused about what fees we need to pay exactly. He applied for me and our daughter and on the CEAC Webside stays an information for fees:

" If you are a US citizen with petitions for your unmarried son/daughter or parent also in process at the national visa center, you only need to submit one AOS Fee for this case and all related Cases."

so now were not really sure what this means and if we miss a fee that means we cant come forward with the process maybe?

Do we have to pay all 4 fees (2 IV fees and 2 AOS fees)?

Do anyone know or have experience with this?