With today’s technology, you can prevent crooked teeth in your children. Your dentist may suggest two separate procedures to prevent a misaligned bite or overcrowded teeth, which cause teeth to shift

Key takeaways:

• Phase one, or initial treatment, aims to create a strong foundation for healthy adult teeth to come through, usually when your child is around 8.
• Phase two usually involves fitting braces to help guide adult teeth into permanent position.
• If initial treatment was successful, adult braces may not be necessary.

A child should see a dentist before the age of seven for assessment on risk of orthodontic problems.
"Two Phase orthodontic treatment won’t be necessary for every patient..."

More:
https://yourdentalhealthresource.com/is-two-phase-orthodontic-treatment-right-for-my-child/