Four years on from his family's ordeal, it is clear Jon is still haunted by the experience.
Yet he and others who had similar ordeals return to the unit, within Hull Royal Infirmary, each week to support others.
"I want them to feel like they're not alone, that there's someone to talk to, someone who understands," explains Jon.
"If I can make a difference to one dad, then I've done my job."
Although not criticising the standard of care, Jon explains dads on the unit can feel isolated and unable to share their emotions during what is often a highly traumatic period.
During Ralphie's five weeks in NICU staff would tell him and his partner to go home for rest.
For a moment, Jon is transported back to 2020.
"We'd get home and we'd have a phone call saying he's struggling with his breathing and his lips have gone purple and to get back quick," he says.
"So we're then quickly putting our clothes back on and in the car and driving like crazy back to the hospital, thinking will he be alive when we get there?"