Naya Rivera lived for her son, Josey. ET’s Kevin Frazier sat down with the late actress’ father, George, for an emotional conversation nearly a year after her death last July, and he talked about how Naya changed after becoming a mother.

Naya gave birth to Josey, whom she shared with her ex-husband, Ryan Dorsey, in September 2015. George told ET that Josey was definitely Naya’s number one priority.

“He really became everything for her,” he says. “Her focus was really on him and he was growing up as she was becoming a mother, she really leaned into that, really leaned into that and the word I want to use is maturity. She became very mature as a person and really receptive to other people’s feelings.”

“I watched the maturity in her after she had a child, before and after, big difference,” he adds.

Naya was pronounced dead on July 13, five days after she went missing at California’s Lake Piru while taking a boat ride with Josey. Authorities later shared that they believed that just before Naya’s death, she mustered enough energy to push Josey safely back onto the boat as the boat started drifting, though couldn’t save herself. When asked what that final heroic act says about Naya, George shares, “Sort of the same mantra she used for life, you know, preservation, keep going, when things are hard, you keep pushing. It just shows you the strength of the person.”

George says the now 5-year-old Josey does frequently ask about his mother and they don’t shy away from the conversation.

“He says, ‘Oh, I used to do this with Mommy. Oh, I remember Mommy used to do this,'” he shares. “It might be a cup out of the cupboard, it might be a snack and we go, ‘Yeah, remember when you did that?’ We don’t back off of that, we just keep reinforcing his values and our values.”

“Tough situation, especially because he was there — it’s not like you’re talking about a ghost that’s floating around, right?” he adds. “He’s got memories as well, but boy is he coming around, right? Really strong kid. We handle him and we talk to him just like he’s a 5-year-old going on six. It’s no different but when he wants to talk about his mother, we talk about his mother, in conversation. He’s growing up and handling it really well.”