Greene, a brightly effective author of juveniles, applies her savvy with youthful gab and gripes to this pleasant, somewhat marshmallowy situation-tragedy--in which a 16-year-old boy and his family, out of touch with one another, find a new unity and stronger ties of love. . . when the father is stricken with terminal cancer, John Hollander dreams of making it big as a Woody Allen-style gagster; he worries about his sexual equipment, wishes he could be flamboyant like his grandpa ""Grandy,"" and is tired of being nagged about goofing off at school; above all, he wishes he could really talk to father Henry. John looks forward, then, to visits from college-student sister Leslie (the family's peacemaker/jester) and gets some flaky support from pal Keith--who has his own terrible problems. (Keith's mom is a promiscuous boozer, and they're both somewhat suicidal.) And when Leslie does come home, she brings the fascinating Emma--who miraculously gets John to actually ""do it."" (Wow!) In the meantime, however, Henry gets the terrible news from his doctor, travels to Texas for another opinion, and finally tells wife Ceil and the rest of the family. So, during the suffering that follows in the six months that Henry has left, other worries pale in the imminence of loss. Leslie, who had planned to travel to Saudi Arabia with a boyfriend, changes her mind; John now understands the ""bravery"" Grandy sees in Ceil and Leslie; Keith, gradually drawing closer to the Hollanders, begins to see the value of cherishing life. And in one small-hours session of card-playing, the three Hollander men--John, Henry, and Grandy--exhibit old wounds, cauterize them, and openly express love. . . before the family's last meal together, outdoors in a spring evening. (John knows this is ""the last time they would love life as much as they had before."") Sentimental, true, but enlivened by teen quips and claasroom/blind-date humor: an upbeat family tale, YA-oriented.