If you have more than one Instagram account, you can only apply your phone number to use 2-step authentication to ONE of your accounts.
When you go to apply 2-step authentication to a second account, Instagram will let you do it, but it will turn the 2-step auth you applied to the first account OFF… WITHOUT notifying you!
So, you either need:
1. a unique phone number for each account you apply security to; or
2. to use an AUTHENTICATION APP to apply the security to both or the second account.
Why is it important to increase your security using 2-step or 2-factor authentication?
…I personally don’t post photos of my small children on Instagram, but if I did – that would want to make sure I stay the boss of those photos.
If you give away ANY personal details on an account – THAT would be a good reason to want to increase security on the account.
Your Instagram Influencer account would be annoying to lose, and a personal account could be personally damaging by someone who is willing to exploit your children/family.