Walkthrough for My Sisters Keeper of Red Dead Redemption.
1. Go to L mark in the Map to meet Luisa Fortuna.
2. She works from 5AM to 2PM, so you can only visit her at between that times.
3. Get on the Wagon and drive to the Yellow Dot as fast as possible. Be careful with horse's stamina.
4. Use Dead Eye to kill as much as possible on your path but never stop.
5. For the direction, listen to the girl and keep looking at the mini-map.