Reese Witherspoon and ex-husband Ryan Phillippe just pulled off a rare reunion ... showing up all smiles for son Deacon Phillippe 's graduation from New York University! The former couple looked every bit the proud parents Friday as they snapped pics and celebrated Deacon's big milestone in NYC. Honestly, Reese and Ryan may be Hollywood royalty, but they blended right in with the sea of emotional parents soaking up graduation day. Still, seeing these two together is pretty rare these days ...