<p>For additional info, I would just say that you weren’t involved in extracurricular activities because you had to take care of your (I’m assuming baby) brother.</p>
<p>You definitely should not put an objective down for a resume, because you’re not applying for a job. Things like an objective aren’t appropriate for applying to college. I don’t really recommend attaching a separate resume anyway–the Common App should be enough to list your most important activities, awards (if any), and work experience. If you do decide to attach a resume, include everything. For the extracurricular activities you might want to just put “See attached.”</p>