A celebrity-sighting in the Back Bay? Oh, but it’s true: Funny Girl/Friends cougar Marlo Thomas was spied signing copies of her new autobiography at the Back Bay branch of Lucca yesterday, per the Globe. Her memoir’s called Growing Up Laughing (which is decidedly more palatable than Throwing Up Laughing, which is how we originally read the title). Hometown designer Denise Hajjar hostessed the soiree. Phil Donahue not seen.