If you have claimed the dependent on a tax return in a past year, you can look on an old tax return.
You have to access your own account and/or print it for yourself using exactly the same account and user ID that you used when you prepared the return.
https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-access-my-prior-year-return/01/270...
Many people have multiple TT accounts and forget how to access them. Log out of the account you are in now.
Account recovery
https://myturbotax.intuit.com/account-recovery/
https://ttlc.intuit.com/questions/1901535-forgot-your-turbotax-online-user-id-or-password
The child's school or the doctor you go to *might* have a record of the SSN.
Or you will have to get it from Social Security.
SOCIAL SECURITY LINKS
https://www.ssa.gov/myaccount/replacement-card.html
To Replace a Child’s Social Security card
https://faq.ssa.gov/en-US/Topic/article/KA-02723
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
