Maleesa Mooney died from “homicidal violence,” according to the Los Angeles medical examiner’s office

Maleesa Mooney. Photo: Jourdin Pauline/ Instagram

Maleesa Mooney, the model and real estate agent who was found slain in her luxury downtown Los Angeles apartment on Sept.12, was pregnant at the time of her death, her sister tells PEOPLE.

Weeks after receiving the devastating news, her family is still searching for answers.

“The police haven’t said anything to us yet because of the ongoing investigation, but from what we saw at the coroner and mortuary, my sister was in a struggle and it’s devastating,” Mooney’s sister, Jourdin Pauline, tells PEOPLE. “It’s a very monstrous act. I wouldn’t wish this on anyone.”

“A lot of things just don’t make sense to us,” she says about her sister’s death. “We’re just really trying to get answers. It is horrible. We had to have a closed casket for her two days before her birthday.”

Jourdin, 24, says her sister was loving her life. She was enjoying working as a real estate agent in Beverly Hills as well as a model, and was looking forward to her next chapter as a mom.

She was two months pregnant, Jourdin says.

“She was super excited and I know she really wanted a kid, and it’s something that she has always talked about,” she says, adding that her late sister’s boyfriend is “heartbroken.”

Days before Mooney was found dead in her downtown Los Angeles apartment, her family grew suspicious on Sept. 7 when Mooney didn’t return calls or texts. Jourdin and her mother had plans to meet up with Mooney that upcoming weekend to help them move into a new home.

At one point, she says, it looked like her sister’s phone had turned back on.

“We’re like, ‘Okay, maybe she just broke her phone, it’s charged now,’ or something like that. It started to deliver, and then that gave us hope. We’re like, ‘Okay, she’s okay.’ And then, still nothing. No one was hearing from her.”

Jourdin says her mother got her daughter’s call records and phoned the last number she called. She says someone answered the phone and said a person had tried to sell her phone to them for $100.

Nichole Coats. GoFundMe

“Whoever had her phone was trying to sell her phone,” she says. “And her last call was made to the person who was trying to buy her phone. So my mom calls the last number because she’s like, ‘Okay, we can’t get in contact with her, so maybe this person knows.’ And the person on the phone was like, oh no, someone was just trying to sell me this iPhone for a $100.’”

Jourdin says they went to the apartment to check on Mooney but they weren’t allowed to enter so they waited for police to arrive.

“When they swung the door open, it was a cold breeze in her apartment,” she says. “It was flooded, was covered in water, like the entryway up into the living room. We’re like, what the heck? Why is her apartment flooded? Then they just told us to go downstairs and then we waited for hours.”

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They later discovered that Mooney’s laptop, phone, her dirty laundry and favorite purse were missing.

There was “black dust everywhere for fingerprints,” she says about entering her sister’s apartment after police left.

“It was honestly so chilling,” she says. “I’ve never experienced anything like that before. Different parts of the carpet were ripped up and the refrigerator was gone. Whatever happened that night was very scary and traumatic. I know she was so scared. I just hate to think about it.”

Mooney had just moved into the luxury apartment less than one month earlier.

“She just bought all brand new furniture, beautiful decor for her home and she couldn’t even enjoy it,” says Jourdin. “It was such a cute apartment and it’ll never be the same.”

‘We’re Going to Get Justice’

Jourdin says she won’t stop searching for justice until her sister’s killer is arrested.

“We can’t let this rest,” she says. “It could save the next woman’s life. If you do it once, I’m sure to this caliber, you have it in you to do it again. So, whoever did it, they need to be prosecuted. We’re going to get justice.”

But she is frustrated with the lack of information released by the police.

“We don’t even know who we’re looking for,” she says. “The police haven’t released any pictures. If it was a guy, if it was a woman. Hopefully we have a new lead and they post a picture and we get something so we could know what we’re looking for and just who we’re looking for. I need more steps to be made instead of just sitting on our hands.”

LAPD Says Deaths of 2 Models Found Days Apart Are Not Related

Mooney died two days after 32-year-old model Nichole Coats was found in her apartment in downtown Los Angeles. The Los Angeles Police Department has since said their cases are not related.

“I just want us to really keep an eye for all those things and all those red flags just in case,” says Jourdin. “I just want people to be aware of the situation and take precautions to be safe, and share your location with your loved ones, and tell someone close to you what you’re doing that you trust. And just be aware and just be safe out here.”

Mooney’s funeral is planned for Oct. 14. The family had to “hire a special person to come in and put her together as possibly good as they can, and we’re still going to have a closed casket, because I don’t want anyone to see her in that type of condition,” says Jourdin. “I don’t want anybody to remember her like this, you know?”

“She taught me everything, everything I know,” she says about her oldest sister. “She taught me how to drive, taught me how to put on makeup, taught me everything. Taught me how to dress, taught me how to walk in heels. We’re supposed to be growing old and going to each other’s weddings and having kids and it’s not the way it’s playing out. It’s just not what anyone expected and it just sucks. It sucks so much.”

“I just can’t wrap my mind around this ending,” she adds. “I feel like she’s here with us though. I’m smelling sweet smells. The other day my shoulder started to smell like her. And I’m like, ‘How does my shoulder smell like her? Did she just come hug me or something?’ And I know that the sweet smells is an indication that she’s around.”

The smell, she says, is of Chanel and flowers.