Hi @JoCrow59, let's jump right into this!
At the moment, it won't be possible to transfer the ownership of the Family plan to another user, since the payment (and whatever features the plan now has) is only associated with the account that was upgraded.
If however you have access to your husband's Dropbox account, and email address, it might be possible.
Keep in mind that to change the manager of a Family plan, the subscription will need to be cancelled first, in order to re-upgrade under another manager later on.
Thanks a bunch!