Need Advice to create two account at the same time !!

Hi

i want to create two account at the same time for student and parent

where student register his account create also account for his parent where parent username will be like his son username but with PT at the end

for example if student user name is adam his parent username will be adamPT and get random password

also i want to insert data in student and parent table

Student table: contains fields:

Id (PK), uniqueidentifier

FirstName , .......

Parent table :

Id (PK), uniqueidentifier

StudentId (FK) uniqueidentifier

FirstName , and another data

so when student account created i want to create account for his parent and insert in student and Parent table

Note: i'm using membership

i want to know the best and easy way to do this

Thanks
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