HOUSTON -

An amber alert is in effect for a 4-year-old girl in Texas after her stepfather said she was kidnapped. Maleah Davis has not been seen since Friday night. Her stepfather said he had pulled over on the side of a road when two men attacked him and took her. 

The intense search now in its fourth day. We're now hearing from the little girl's mother, who said she just wants her home.

"It's like a nightmare. It just keeps going and going," said Brittany Bowens, Maleah's mother. She said she is distraught over her daughter's disappearance.

"What would you say to your daughter right now?" CBS News' Janet Shamlian asked.

"That mommy loves you," Bowens said, crying. "And I'm sorry this had to happen to you."  

Stepfather Darion Vence was the last to see Maleah Friday night, telling police he was on his way with Maleah and her younger brother to pick up Maleah's mom from the airport. He said he pulled over thinking he had a flat tire and then was approached by two men in a blue Chevy pickup. 

"One of them makes a comment saying Maleah looks very nice, looks very sweet. The other male hits Darion in the head," Houston police Sgt. Mark Holbrook said. 

Vence allegedly told police he was in and out of consciousness, at times in the back of the suspects' truck with the children. He said when he woke up around 20 hours later on a highway, he had his young son in his arms – but no sign of Maleah. Houston police have not named Maleah's stepfather or anyone else as a suspect. 
 
Police are now looking for the blue truck and the family's car, a 2011 Nissan Altima. It was spotted on surveillance video Saturday afternoon.

Police said Maleah had several brain surgeries. The most recent was last month. 

Family members are passing out flyers and pleading for anyone with information to come forward.

"I have to be strong for her. I have to. I have to believe that she's okay. I have to because it's the only thing that's getting me through this," Bowens said, choking up with emotion.

A team of volunteers from the group Texas EquuSearch joined the effort to find Maleah. They've been searching in the area near where she disappeared. The group said they are hoping for the best, but expecting the worst.