I didn't know Floyd had a daughter as well as a son
I've seen 2010 more times than 2001, and I knew that Dr. Heywood Floyd had a young son who liked to play with the family dolphin and to whom he described suspended animation to before his mission, but I clean forgot he had an older daughter, too, who he calls from the space station about her upcoming birthday.
I guess such things are overlooked in movies decades apart and with different actors.