Would appreciate any ones help or advice!!

We have a website for our business where customers log in and book their children on to an activity course.

At the moment they have to re enter the childs data every time they want to sign up for the course, however what we'd like to do is create a profile page for the parent which will allow them to enter childs data which will be saved on to a database.

So when they re sign up to the course each time they can select their child or children from a custom generated mysql database for that profile, which will automatically enter their data in to the booking form.

I have created the form for them to enter their childs data but i'm unsure as to what the correct php and mysql coding should be for both the childs data collection from the form and the input of data into the booking form.

If you need any more information from me please let me know!

Any help would be much appreciated!!!

Keeping it simple.
Add columns to the table which you store your users, columns could be for example child1, child2, child3 etc.

Create another table for children with columns for example idnumber(auto increment primary), name, age, eye color, bla bla.

Then when user registers, you send the information about each child to children table and store the idnumbers in an array. Then you will in the user table with the user information(username, password etc) and then fill in the children columns with the array.

Then when user wants to register a child on the page designated for that, you fetch the child idnumbers from his user table and store it in an array, then you make another query fetching the info on each child according to the idnumbers in the array.

Post your DB structure here. It will be easy to analyze.