Reynolds and his partner Tahan Lew Fatt welcomed son Ryu early back in January.
Speaking to media after the race, the 35-year-old elaborated on his newfound sense of responsibility.
"Pay for them, kids are expensive," he joked.
"Not really. I just want to do everyone at Penrite proud and everyone at the team proud.
"I just say that for s**ts and giggles. That’s it."
The result was Reynolds’ 31st podium, and the first for his team under its Kelly Grove Racing guise.
WATCH: UNWELL REYNOLDS' SANDOWN HORROR
Reynolds’ high-profile departure from Erebus Motorsport ended a bright relationship with he team he recorded 19 podiums with between 2016 and 2019.
The move to KGR has already paid dividends, with Reynolds lying ninth in the standings heading to next month’s Beaurepaires Sandown SuperSprint.
The next milestone remains a first win since Newcastle 2018, but the new father was pleased he is making his move to KGR work.
"It was awesome today to get a podium in my 350th race at the Penrite Oil Sandown Super Sprint and do everyone at Penrite proud this weekend and bring home a trophy," he said.
"It was shocking conditions, especially at the start, but I got a good start, moved up to P3 and then just kept my head down from there.
"It’s a really solid improvement from where we were last round, we were competitive all weekend and the car was pretty good to drive, particularly today.
"The first race today was pretty disappointing because we got turned around and the car was damaged, which is a little annoying because the car would have been just as quick in that race.
"We’re heading in the right direction as a team and I’m really proud of all the guys, it’s been an intense few weeks with a lot of changes to the cars but it’s started to pay off."