Baby Lisa Irwin
A handout picture of Lisa Irwin Reuters

It has been one month since baby Lisa Irwin disappeared from her parents' home, and no one has been arrested so far. Even the police have no solid information about what has happened to the child.

Vikki Ziegler, one of the top family lawyers in New York, said that if the parents of the missing 10-month-old baby were not involved in her disappearance, then they should be helping the police with the investigation rather than refusing interviews with them.

Ziegler said the story of the infant's disappearance, as told by her mother Deborah Bradley, had changed over the weeks since she went missing Oct. 4.

During the early investigation, Bradley, in an interview with NBC's Today, said that the police thought she killed the baby and was expected to be arrested. However, later in the interview, she admitted that she was drunk on the night Lisa disappeared.

If you drink and pass out, it's not a crime, Ziegler told Hollywood Life. But the couple was not talking more than they should to the police, she added.

The police, with the help of a sniffer dog, found the scent of a dead body in one of their rooms. But they could not find the dead body.

Ziegler said she believed Deborah Bradley and her husband Jeremy Irwin were hiding something. She said the couple was supposed to protect their daughter and not themselves. Because she's not doing that and acting so bizarre, you want to kind of point the finger at her and say 'Something's not right,' she added.

Ziegler said a close look at the case would suggest that one of the family members had something to do with the child's disappearance.

In an interview, Bradley said that she feared being arrested and if that happened, then the search for Lisa would probably end and she would never make out what happened to Lisa. But, according to Ziegler, Bradley was staying away from the police because she had something to hide.