Setting the scene:
The key to decorating for this party is to embrace the term "modern" so tightly that its eyes bug out. Go with clean, crisp, suburban modern furniture you purchased from Overstock.com. On that slab of a walnut coffee table you bought, put a world atlas and put color-coded pushpins designating countries where you might be interested in either adopting a child (like Cameron and Mitchell) or choosing a bride (like Jay). Make a wall-sized fake family tree with photos featuring your stepfather's transgender nephew who is now engaged to your recently divorced son. Set up a video camera in front of a couch, and have couples or families tape video confessionals of how they met that you can burn onto a DVD and send to them later. Add a couple of kids bikes, dolls, Viagra and Geritol to the decorative process. Finish things off with a huge banner that says "Congratulations!" What are we celebrating? Does it matter? There's always a birthday, graduation, promotion, divorce or wedding going on.
Have guests dress like their favorite character - which for us would either be Jay (think velour tracksuit), Cameron (definitely go with Robert Graham dress shirts) or Lily (baby clothes).
On the menu:
Let's embrace one of the newer members of the family, Jay's wife, Gloria, and feature cuisine from her native Colombia. Serve fried red snapper with fried plantain and coconut rice with red beans. Serve a nice Chilean wine.
On the hi-fi:
Have a little something for everyone on this mother of all mix tapes. Make a game out of which song is dedicated to whom. Go West by the Pet Shop Boys, Love and Marriage by Frank Sinatra, Wouldn't It Be Nice by The Beach Boys, Marry Us by the Boston Gay Men's Chorus, I Will Remember You by Sarah Maclachlan, There Goes My Life by Kenny Chesney.
Nothing says family celebration like a trip to Walt Disney World. But the modern family prefers to keep things moving, so book the entire clan on the Disney Magic, a 964-foot cruise ship that accommodates 2,400 guests, many of whom are Goofy.