<human>: Hi reddit, I apologize if any formatting is weird, I'm on mobile.

I have a younger half brother (we will call him N) by my dad and I'm not sure if he knows about me. The mom, (we'll call her K) knows I exist. 

When my parents were married, my dad cheated on my mom with a one night stand and N was born on the same birthday as my mom. Needless to say, she wasn't happy. They've been divorced since I was 8. 

K had a restraining order on my dad that was set a year and a half after my brother was born. She never issued child support. K and her husband are still together as far as I've seen on Facebook. My brother took their name (it's an oriental name) and he's a little white boy. So as far as I know, he knows that the husband isn't his dad. 

I'm wondering, should I message K and ask about my brother? If he knows that he has a half sister? I know there's the possibility of her never wanting me in his life. I've met him when he was a baby, and even have a picture of N, my dad and I together.

Condense the text into a few key points
<bot>: found my half brother and his mom, considering messaging her, not sure if brother knows about me. How should I go about this?