I was able to find little detail about most of the orphans.
- Mary Murphy, age 13 (orphan): Went on to California and married 3 months later. She later divorced and remarried, settling in Marysville, California, which her second husband founded and named for her.
- William Murphy, 11, (orphan): returned to Missouri (presumably to live with family) and went to law school, then settled in Marysville, California.
- Mary Graves, 20, (orphan/adult): went on to California and married 3 months later. Her husband was murdered a year later and his murderer was the first person executed under California law.
- Mary Donner, 7, (orphan): was adopted by a couple in California
- Eliza Donner, 3, (orphan): lived with her married older sisters
- Georgia Donner, 4, (orphan):was adopted by a couple in California
- William Hook, 12, (orphan): died from overeating shortly after rescue
http://www.donnerpartydiary.com/survivor.htm
http://www.sfgate.com/bayarea/article/What-happened-to-the-survivors-of-the-Donner-6837732.php#photo-9419004
https://www.sierracollege.edu/ejournals/jsnhb/v4n2/houghton.html