Brady couldn't be more proud of his son ... with the proud father showing off on Instagram about his kid's new gig.
"Buccaneers got a new ball boy this week," TB12 said. "He takes his summer job and every rep very seriously ... just like his dad!!"
No word on if this is a full-time summer job for Jack now, or if it was a one-time thing ... but either way, it's very cool to see.
Of course, TB12 and Jack have spent a lot of time bonding over football together over the years ... remember, the QB juked the hell outta his son during a backyard workout back in 2018 -- which is just as hilarious 3 years later.
As it turns out, Jack has a birthday coming up ... so have a good one, kid!!