Just an update, I sent an email asking them about this situation, and just got a reply pretty quickly:
Hello,
Thank you for contacting our office.
Your daughter does not need to attend her citizenship ceremony, as clients under the age of 14 do not need to be present for the oath taking. Please make sure to have your daughters IDs as well as your own (ie. PR card + health card/passport) as you will need to cut her PR card during the ceremony check in.
Warm Regards,
IRCC Official / Représentante d'IRCC – TP
so the answer is, no, kids are not mandatory to take the oath even if you mentioned in your app form under the question 10.
Excited to be Canadians soon!
Cheers!