The search for missing baby Lisa Irwin continued Sunday as police teams searched near Interstate 435 and Parvin Road near Kansas City. Baby Lisa's parents, Jeremy Irwin and Deborah Bradley, continue to maintain their silence in their missing daughter's case.

While police refused to reveal what information led them to search this area, KCTV-5 reported police have not conducted a major search of this particular region since mid-November. It is unclear why police decided to revisit the area in search for baby Lisa.

Fox 4 reports that independent volunteers continue to search for baby Lisa as well. Over a dozen volunteers searched an area near Interstate 35 and Chouteau on Sunday. The group targeted this area because of its proximity to Irwin and Bradley's home, reported Fox 4.

We are searching for clues for baby Lisa so we can bring her home safely, one volunteer, Edith, told Fox 4.

At that point when they were searching, there was a lot more vegetation, another volunteer, Shelly, commented. The volunteers remarked that the landscape in the area has changed in the past few weeks due to the weather and may leave clues more visible.

We just can't let it go, she continued. I mean, you know, a baby doesn't just vanish you know.

They could throw stuff over, looking on hills, throw cell phones out, Edith continued. If they are changing the baby they could throw her clothes out.

As a mother and a grandmother, I can't let it go, Shelly told Fox 4. I mean, I feel like there's not enough people out there seeing her face. She's defenseless, innocent baby, she's somewhere.

Lisa's father, electrician Jeremy Irwin, returned home to find his daughter missing on Oct. 4, 2011. He called 911 to report the disappearance of baby Lisa immediately.

A window and screen were tampered with, lights were left on, the family's front door was unlocked and three cell phones were missing. Deborah Bradley claimed she last saw her daughter at 10:30 p.m. before falling asleep in bed with her two sons. Bradley later admitted she had been drinking wine and may have been drunk the night her daughter disappeared.

Bradley and Irwin have been uncooperative and have refused to be interviewed separately by police. Lisa's parents have now asked that supporters cease their candlelight vigils and have expressed hope that their life can return to normal. Onlookers wonder how the parents can even hope to live a normal life when their 1-year-old daughter has been missing for over three months.

A $10,000 reward has been offered for information related to finding baby Lisa from an anonymous donor.

Authorities continue to maintain they have no major suspects or leads in the case. Investigators closed an outpost dedicated exclusively to solving baby Lisa's case in late November and authorities are now addressing the case in their main offices in Kansas City.

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