One would have to be from Reunion.
Worf and Alexander are in Worf's quarters alone. Worf tells him that he made arrangements for Alexander's care, but Alexander
asks why can't he stay with Worf.
Worf gently explains that he deserves a home and family which his parents can provide. Alexander looks off into the distance.
Worf senses what Alexander is thinking, tells him, "I miss her too."
Then Alexander looks up at Worf and slowly asks,"Are you my father?"
After a second, Worf finally softens up and admits, "Yes, I am your father".
Alexander reaches out with a hand, and Worf takes it, and pulls him closer and they embrace.
It was a wrenching moment that nobody else aboard would ever find out about.