Why child with investment income appears in my son's CA state return when it has nothing to do with the CA income he got for a summer internship?

[KrisD · Accepted solution]

If your son is your dependent, and he was in CA for an internship, be sure he files as a resident of the state in which you live and as a non-resident of CA for the internship income. 

Dependents must be resident of the same state in which the taxpayer that claims them lives.