You can add both parents onto a child's record as Contacts, with both sets of email and phone numbers.
Go to the patient's General page by clicking their name from the Patient List or from an appointment.
In the Contact Details section, click Add Contact (to the right).
Select the Relationship type (such as Father).
Select the Contact Type (such as Emergency or Next-of-Kin).
Enter the name of the contact and select their name from the drop-down list. If the contact is not a current patient or if they do not have an existing record. select to add them as a new contact / patient.
Complete the rest of the details and select "Enabled" under Reminders if this parent is to receive appointment reminders.