In th final showdown with the Russian mercenary type bad guy, he goes on about how he "did good work" for the Grandpas' agency pals back in the 90s
Also the Grandpas' squad is called The Devil's Scum, which is impossible not to hear as The Devil's Cum ever time it's spoken. Had to be intentional
Finally a movie that is unapologetically for kids and their grandpas. Dumbass moms and dads stay home you wouldn't get it