Verification code for family sharing

I got an Apple credit card in order to get the cash back for Apple purchases, so it is the primary card on my Apple ID. We use family sharing, so my husband and children have access to this card. Typically all of them use Apple gift cards for their "allowance", which I purchase and send to them. Since adding my Apple credit card as my primary payment on my Apple ID I have to provide them with verification codes for them to make purchases on their Apple ID- even if they have funds available in their account from a gift card. This is obnoxious- my husband and oldest daughter do not need me to verify their purchases, especially if they have funds available in their own account and it is not being charged to my Apple credit card. Is there a way to turn this function off?