Yes, multiple practitioners can create "profiles" for the same client in Practice Better. Although we require a unique email address for each client in your account, there is no restriction preventing other practitioners from adding and inviting a client with the same email address that existing in your records.
If your client already has access to the Client Portal and is invited by another practitioner (Practitioner B), your client will receive an Invitation email from Practitioner B that will allow them to activate their account in Practitioner B's portal:
Once your client has clicked on the Activate My Account button, they will be prompted to sign in to link their existing login credentials to the profile created by Practitioner B.
Your client will then have access to both Practitioner B's resources and your resources when she signs in. They will see a profile picker prompting them to select between you and Practitioner B: