How to allow parents to register children but still record their own info
If you're using Drupal, Webform-CiviCRM Integration will handle your scenario pretty easily. It allows registering any number of participants for any number of events on a single form.

You may also want to e-mail Sarah Gladstone, the author of the Youth Registration extension, what she uses instead - but I'm pretty sure they use Webform-CiviCRM integration these days.