As anything else, this is another personal decision to be discussed by the couple.
I believe there is not right or wrong answer. Each couple will have their circumstances, preferences and little humans or not to celebrate with.
If the answer is "YES, we want them in both our ceremony and reception",
then it is quite easy: just include them on the invitation.
"The Smith Family"
or name each person:
"Marina, Adam, Charles and Sue"
If the answer is "NO, we rather this to be an adult celebration", below you will find some polite ways to word your wishes.
How do I kindly request NO kids to my wedding?
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