Iberia Plus has launched an offer which awards 2,500 free Avios for getting your children to join their new Iberia Plus Kids program. 2,500 Avios may not be much on their own but you should be able to transfer those points to British Airways Executive Club after those points have been in your kids Iberia account for 90 days. Of course, once those points are in your child's BA account you can create a household account where all the Avios points are shared by that family. So if you have a lot of kids (just think of 19 kids and counting or is it 20 now? ) this can be a good way to rack up a lot of free Avios points! Now, the sign up process is a bit convoluted in that you have to fill out a form and send it in via email, fax or post along with copies of your child(s) passport. But if you have 4 kids you can get 10,000 Avios which is enough for an award ticket between Toronto and New York once those miles are in your BA household account.
If you want to take advantage of this offer, you can sign your kid(s) up for Iberia Plus Kids here