Back in 2011, there were several articles that covered this territory. One of them mentioned that none of the co-workers knew he had a grandson. She had no pictures on her desk in the manner a grandmother normally would. What I have posted is the ghost of just one article which did exist at the time.
Most of those other articles are gone, either succumbing to the dead link disease, or deliberately scrubbed.
Maybe. But you can't build whole theories on half-remembered, possibly partially accurate reports and expect them to stand up.
Younger colleagues thought Dunham was a tough old school old lady. She wouldn't have become a VP if she wasn't. She naturally didn't talk to them about her private life. There doesn't have to be anything more to it than that.