(WRCB)- A 25-year-old mother of four has been missing for five months. Investigators are searching for clues in her disappearance. Erica Whaley was last seen getting into a red truck at a shelter for battered women.

Whaley's mother and sister are speaking out, asking for the public's help in finding her.

They say 25-year-old Erika Whaley has been known to "do her own thing," going off on her own for periods of time. But they say she always maintained contact with them.

Now it has been five months since they have heard from her. They say they are very scared and worried.

"I don't know what's happened," says Letitia Curtis, Erika's mother. "I just want help finding out where my baby is." She says it has been five months since she has heard from her daughter.

"I talked to my sister at times on a daily basis. Sometimes once a week," says Erika's sister, Sandra Lowrance.

Lowrance says it is so hard not knowing where she is. "There's no words to describe how we feel," she says.

Sandra and Letitia say the last time they heard from Erika was at the beginning of September.

They admit she has a troubled history. Erika was staying a women's shelter in Chattanooga after a dispute with her estranged boyfriend. Staff at the shelter say she was last seen getting in a red truck with an unknown man.

Letitia says after a month went by she contacted a missing person's hotline.

"She said that one out of one thousand people are actually missing, to give it a little time. So, and two that made me think she may be off doing her own thing. Maybe she met someone new, I didn't know," says Curtis.

Erika has four boys, ranging in age from three to seven. Once birthdays and Thanksgiving passed, Letitia knew something was not right.

"She's a grown woman, she can do what she wants. But not to contact her children? She's never been that way, she loves her kids," says Curtis.

They have taken to her Facebook page letting her know they were contacting police but still, nothing.

"I don't care what she's doing, I don't care how bad it is. I don't care what it is, I love her and I want her home," says Curtis.

She and Sandra have a message for Erika: "Please call us! We don't care what you're doing. Just come forward and call your family. We need to know what you're doing. We need to know you're ok."

Whaley was officially declared a missing person by police on December 16th.

She is described as being very tiny at 4'11", 115 pounds. She has brown hair, maybe with some blonde highlights.

If you have any information in this case, call Chattanooga Police at (423) 698-2525.