"Tacopina and I were not able to work as a team," attorney Cyndy Short said at a news conference today. "Our goals and our approaches are so different that one of us had to go."
Short was dismissed shortly after she gave media tours of the Irwin home, which the family now says they learned about after the fact.
"After hearing there was a press conference and listening to Mrs. Short's statement, we are further convinced that we made the correct decision," parents Deborah Bradley and Jeremy Irwin wrote in a statement e-mailed to ABCNews.com. "One of the reasons we relieved Mrs. Short was because she was holding her own press conferences, making statements to the media, and giving tours of the home that we were finding out about after the fact."
The family also wrote that they learned the FBI felt Short was not "productive" in their relationship with the family.
The family said they wish the focus to remain on the search for Lisa and that Tacopina has secured "very prestigious local lawyers to join the team representing the family."
Short said she had been working pro bono for Bradley, 25, and Irwin, 29. Short said she did not know where any of the money was coming from to pay the family's legal bills or any details about the benefactor who is offering a $100,000 reward for finding Lisa or finding her abductor.
Lawyers for Baby Lisa's Parents Split
"When I got involved in this case, I did it to stand up for Jeremy and Deborah and to prevent any kind of wrongful arrest or conviction," Short said.
The police investigation so far has centered around the parents. The police have complained that the parents aren't cooperating, and last week planned interviews of the couples' young sons were cancelled at the last minute.
In return, Tacopina and Short has criticized the investigation.
Short said she believes 11-month-old Lisa was "stolen" from her home and maintains that Bradley and Irwin are good parents.
"I know that Deborah and Jeremy are a loving couple," she said. "Everything I've seen about the way they treat their children and the loving home they've created tell me that they are caring parents."
Short said she felt "an advocate was required" for the family "because of the way the press was painting things and also because the relationship with the police was so tense."
Short said she was no longer the family's attorney or liaison for the family with the police or media, or the family's public voice.
"My team is very saddened that we are no longer serving the family as we did in the last 10 days," Short said. "However, we still care very much about them and will continue to be available to them, even if we are not allowed to see them or talk to them."
Short commented that while Tacopina was in Rome, she was on the ground in Kansas City working on the case.
"I contacted them and the last thing we talked about was the love we felt for each other and that they felt they needed to stay with Joe," Short said. "I made it very clear that it was not going to work for me to work with him. Joe and I make different choices and we have from the beginning. Therefore, he's in and I'm out."
Tacopina did not immediately respond to requests for comment regarding Short.
Baby Lisa's Parents Fire Lawyer After House Tour
Tacopino also evaded questions on "Good Morning America" today about whether the postponed interviews with Lisa's 5 and 8-year-old brothers would eventually take place.
"I'm not going to give a date of an appointment or whether or not there is an appointment," Tacopina said. "Every necessary interview will be had with law enforcement."
Tacopina said he believed investigators should focus on the three witnesses who said they saw a man carrying a baby in a diaper the night Lisa disappeared. He called this "vital information." He also insisted that Bradley and Irwin have been cooperative.
"We have agreed to do everything that they've asked us to do, as long as it's being done in good faith," Tacopina said. "What has happened here in this investigation is that the investigation has become a little too adversarial."
"I'm representing two victims," Tacopina said. "I'm a victim's advocate attorney in this case. I'm not a criminal defense lawyer. They're not charged with anything."
Baby Lisa has been missing since the night of Oct. 3 and her parents maintain that she was kidnapped from her crib. Police have investigated nearly 1,000 tips and leads, but have not named any suspects.
Tacopino said the search for Lisa needs to be expanded away from the home.
"The police are frustrated because they can't find answers," Tacopina said. "I have no problem with them looking at the parents and focusing on them, but don't narrow your investigation to the point where that's the only scenario they want to look at."
Tacopina left the relative's home where Bradley and Irwin had been staying and went with the parents to an undisclosed location.
An anonymous benefactor is offering a $100,000 reward for her safe return or the conviction of whoever took the little girl.