That's why I gave the conditions. If the interview is done right, then it could be helpful. I am just saying that in a (very) similar case to this one, the father was vilified, was the only REAL suspect LE focused on (ignoring other clues), he was actually railroaded into falsely confessing to the crime, etc. In short, LE was sure he killed his baby, and were prepared to do anything to prove it. He didn't and only after HE was cleared (8 months of horrific prison - being incarcerated as a baby killer is what nightmares are made of), and only after his lawyer made an incredible discovery was he freed. And even then, people on message boards were saying that to find the killer, all he had to do was look in the mirror. Only after the real killer was actually found and tied to all the REAL evidence, did some people finally accept that he was innocent.
I am NOT saying this family did not do something - just pointing out that it DOES happen. And, had it not been for a damned good lawyer and some incredible luck, Kevin Fox would probably be on death row today.
ETA: sorry, I am passionate about the Fox case. I forgot to explain how this tied in with interviewing the children. IF LE is absolutely sure that the mom is involved, the children could be manipulated into saying something incriminating, true or not.