Transcript for 'I just want them back': Man speaks out about missing wife, children
We are also following the desperate search for a pregnant mother and her two young daughters, disappearing from their home north of Denver. The father saying he last saw his wife Monday morning after the two had a, quote, emotional conversation the night before. Tonight, the FBI joining the case, and here's ABC's Clayton Sandell from Colorado. Reporter: Police tonight are canvassing a small town with a big mystery. I'm worried for everybody. Reporter: Desperate for clues in the disappearance of two little girls, Celeste and Bella and their mother, 34-year-old sheanne Watts. We're working around the clock on this case and we will not rest until we have the answers. Reporter: Her husband, Chris, says before his family vanished, he and his wife had some words for each other. We had an emotional conversation, but I'll leave it at that. Reporter: But he says he last saw his family around 5:00 A.M., when he left home for work. If you're out there, just come back. If somebody has her, just please bring her back. Reporter: Friend Nicole says he got worried when sheanne missed a doctor's appointment and would not answer texts. I'm just concerned. If you're hearing this or you're out there, please, please let somebody know you're okay. Reporter: Searches of the home and police dogs have turned up few clues. Friends tell us her phone, keys and wallet were found here in the family home. Local police are now getting help from the FBI. David? Clayton Sandell tonight. Clayton, thank you. And one more note overseas
This transcript has been automatically generated and may not be 100% accurate.