United Kingdom, May 7 -- Gabrielle Union is "scared but excited" about her stepdaughter leaving for college.

The 52-year-old actress has six-year-old Kaavia with NBA star Dwyane Wade - who also has son Ziar, 23, daughter Zaya, 17, and 11-year-old Xavier from previous relationships - and doesn't see how she or her husband will be able to help their teenager when she heads off into higher education.

She told People: "[I am] scared but excited for her. She's an astrobiology major. So we can't help with that. We haven't been able to help with homework since the fourth grade, but we're excited for next year."

The 'Bring It On' star also brought up the age difference between Zaya and her youngest and has enjoyed that the two of them have bee...