As mamas we want our babies to be safe, and that's what makes what happened to Glee actress Naya Rivera and her 4-year-old son Josey so heartbreaking.

On July 13, the Ventura County Sheriff's Department announced the 33-year-old mother's body was found at Lake Piru, five days after her son was found floating alone on a rented boat. According to Ventura County Sheriff Bill Ayub, Rivera's last action was to save her son.

"We know from speaking with her son that he and Naya swam in the lake together at some point in her journey. It was at that time that her son described being helped into the boat by Naya, who boosted him onto the deck from behind. He told investigators that he looked back and saw her disappear under the surface of the water," Ayub explained, adding that Rivera's son was wearing his life vest, but the adult life vest was left on the unanchored boat.

Ayub says exactly what caused the drowning is still speculation but investigators believe the boat started drifting and that Rivera "mustered enough energy to get her son back onto the boat but not enough to save herself."

Our hearts are breaking for Josey and his dad right now. So much is unknown about what happened on Lake Piru but one thing is crystal clear: Naya Rivera has always loved her son with all her heart.

After welcoming her son, Josey, 4 years ago, Rivera said motherhood changed her in positive ways.

"It's made me a much more observant person," she explained in a 2016 cover story for Mini Magazine "[You realize] how truly selfless you become."

In 2017 she told Momtastic her son (who she shares with ex- husband Ryan Dorsey) was the most important thing in her life.

"He's my number one priority," she told Momtastic. She also explained that the thing that surprised her the most about parenthood was the unconditional love she felt for Josey. "You hear about it and you think, 'Well, obviously I'm going to love my child.' But it's so deep. Even after Josey goes to bed, I find myself thinking of him and looking at pictures of him and it almost brings me to tears half the time, because the love that I have for him is so amazing."

In 2018 Rivera told Bravo's The Daily Dish that she thought she was doing a good job at balancing motherhood and her work as an actress and author. "It's always a balancing act, but I am actually pretty good at time management and prioritizing. I think every mom is!" she wrote in an email.

As she had previously told Mini Magazine, the love she got from Josey always made finding the balance so worth it. "Little things like the two kisses he stood up and gave me last night to say thank you for making him mac and cheese from scratch," she said in 2016. "It's a love never found anywhere or with anyone else."

[A version of this story was originally published July 8. It has been updated.]