Chris Pratt, his son, Jack, and Katherine had an evening out in Pacific Palisades Tuesday, including a celebratory dinner at Blue Ribbon Sushi and a movie. Since Chris and Kat just tied the knot on Saturday ... this would be their first "official" family outing.

The trio was joined by some family and friends ... probably still in town from the wedding.

As we reported ... the couple's not honeymooning just yet. They were both out earlier Tuesday working on their fitness at different spots

Chris and Katherine got married at the ritzy San Ysidro Ranch in Montecito after a wedding rehearsal the night before at Rob Lowe's massive estate.

Instant motherhood seems to suit Katherine just fine.