If that is the only income your child had in 2017 and it less than $1050, it doesn't need to be reported anywhere.
However, if your child had more unearned income than $1050, but less than $10,500, then you have a choice to either report it on your child's tax return or your own tax return. To report it on your own tax return do a Search (top right corner) for "8814". Then click on "Jump to 8814" and enter the information from Form 1099-DIV.