Whoa! when I Googled "surrogate" all I got were links to surrogate mothers. It must be a hot topic.
If it is the mother's natural child, it would be a Custodial acct. (Thanks, Judy).
If the mother was appointed guardian of a someone elses child, and the mother was legally appointed guardian, it would usually be a guardian account.
However, it seems that in some states, they use "Surrogate" for both custodial and guardian accounts. Maybe PA is one of them.
It may be that the child is adopted and the account was opened between the time the mother was appointed guardian and before any adoption was finalized.
Yardley, I would simply tell the mother that it does not matter what the account is called, it is the SSN on the account is all that matters and any interest over $0.50 has to be reported.