Does Kiddie tax apply to trading profit? (Not div/int)

[tbt2018]

It seems to have some confusing here: 

Profile from stock or mutual fund buy and sell in a UTMA (due to market up and down, not DIV and not INT), does kiddie tax apply to that? It seems everywhere when kiddie tax is mentioned, it always refers to "unearned" income, which normally is for DIV and INT. If minors trade stocks in their UTMA, does that profile subject to kiddie tax? 

[MinhT1 · Accepted solution]

For the kiddie tax, unearned income includes capital gains.

Please see the definition of unearned income on page 1 of the instructions for form 8615.