I made a tug with the Klaw to rescue Valentina Kerman, who I had stranded in an orbit of the Mun, and bring her back to Kerbin. During reentry, I set the tug's parachutes to fire at a high pressure, and separated from the mun lander craft, as the tug was expendable but Valentina was not.
After watching Valentina splashdown gently into the ocean, I pressed ] to switch through active ships and observe the tug successfully splashdown as well. After the tug had splashed down, I pressed ] again and was aghast when the message "No nearby objects to focus. Use the Map View to select distant ones." appeared on screen.
I recovered the tug, checked the Tracking Station, and Mun Lander had disappeared. In the Astronaut Complex, Valentina was listed as KIA.
How did she die?