The Mystic Music Fest, a free, family friendly afternoon of live music, returns to the Condon Music Shell. The lineup of bands: 1 p.m., Fractal Cabbage, playing 50/50 covers and original songs; 2:30 p.m., the Spittin Vinnies, the band that plays all the songs you know by heart, plus plus originals “Drink to Boston” and “Stripes Can Dance”; and 4 p.m., the Porter Squares, playing originals and some great lesser covered covers (Squirrel Nut Zippers anyone?). The event is rain or shine. The Mystic Music Fest is presented by Robar Therapy Massage.