Athena was preparing to welcome a little girl. She never got the chance.

Athena Georgopoulos was about to become what she'd always dreamed of: a mother.

At 39 years old and five months pregnant, she was preparing to enter a chapter in her life she'd once thought was out of reach.

But this week, that future was ripped away. On Monday night, she was allegedly murdered.

A concerned neighbour called police to report yelling coming from a home in Mount Waverley, in Melbourne's southeast, police said.

Soon after, another call was made. This time the caller suggested it was "more urgent".

Police arrived at 9:50pm to find two bodies. It was Athena and her 50-year-old partner, Andrew Gunn, ABC reports.

The Herald Sun and 7NEWS report Andrew's head was decapitated.

Hours later, police arrested a 34-year-old man, who was with two large dogs, at Westall Railway Station, about six kilometres from the home.

He has since been charged with two counts of murder and will face Melbourne Magistrates Court on Wednesday.

Police believe it was a targeted attack and say the man allegedly involved was known to the occupants at the home, but they're still trying to work out the exact connection.

Photos of the scene show the home graffitied with words including "karma", "enough" and "betrayal". Police are investigating whether this was connected to the deaths.

Homicide Squad Detective Inspector Dean Thomas described the scene as traumatic.

Athena's devastated mother Petty Georgopoulos paid tribute to her daughter, saying she was "feeling broken" by the tragedy.

"My dearest, you left my life so unjustly that I still can't believe it," she wrote on social media, according to a Greek to English translation.

"In the last few days, you were so happy. We dreamed so much about our granddaughter you would bring into your life, and suddenly, everything disappeared in one night.

"A(n alleged) murderer cut the thread of your life and my granddaughter, you were going to bring into our perfect life. No matter how much we love each other, goodbye my daughter."

Speaking to The Age, Athena's family said she was five months pregnant.

"She was so happy. I spoke to her the other night at Petty's house. She was so looking forward to having a baby, because she was 39 [and] she never thought she could have one," her aunt Patty Dilveridis said.

Petty said her daughter was always there for her as she battled health issues.

She told the publication her daughter and Andrew had been together for several years and described him as a caring man who loved her daughter.

Petty said the couple were expecting a little girl.

Athena is the 44th Australian woman killed this year, according to Sherele Moody's Australian Femicide Watch.

Anyone with information is asked to contact Crime Stoppers.

Mamamia has contacted Athena's family for comment.

Feature image: Facebook/athenageorgopoulos.