 Cain lives in Houston, Texas.He has three daughters.Cain has received numerous honors and awards, including NASA's top honor, the Distinguished Service Medal, in 2015; the Presidential Rank Award in 2012, which is one of the highest honors awarded to a civil servant; being nominated for the prestigious NASA Rotary Stellar Award for two consecutive years in 2010 and 2011, and winning the award in 2011; he was a candidate for the SES Rank Award for 2011; he earned the NASA Outstanding Leadership Medals in 2005 and 2011; a NASA Outstanding Contribution award for the Ariane 502 Re-entry Observation Project in 1997; and a Certificate of Commendation from Johnson Space Center in 1996.