<p>my sisters have this medical condition called PKU and my mom thinks it would be a good idea to write about how that has affected our family and me in my college apps. i'm already done with the main common app essay so i'mnot changing that and i guess the only place i would be able to put this is the "additional information" part. so should i include this and if so what to write and how long?</p>
<p>Has it actually affected you in some sort of tangible way? IE, have you not been able to participate in some extracurricular activities because most of your family's money has gone toward medical care? Have your grades slipped because you've been spending your afternoons in the hospital? Etc, etc. If there is a way that you believe that it's affected you that has caused you to be lacking in some areas of your application, then yes, that's fine to put in the additional info section. Remember, they will read everything you give them, so keep it concise and to the point - it's not a place for you to add in a new essay, just explain the circumstances and the effect they've had on your grades/ECs/test scores/whatever.</p>
<p>I was in the semi-same boat next year, trying to decide if it was neccessary to include that my sister has epilepsy, but I didn't believe that had held me back in some area of my application. So I decided not to put it in. (Although one school ended up finding up, because I ended up missing an interview with them because I had to rush to the hospital because my sister had had a grand mal seizure!)</p>