"We were concerned all the time that he could do something," said Chuck Cox about his son-in-law. Because of the court order "we had to let them go. We understood the laws and the policies - it was beyond our control."
Cox also tells Dr. Phil he believes his daughter will eventually be found and there is indeed someone who knows what happened to Susan Powell.
Also appearing on the show are Detective Ed Troyer of the Pierce County Sheriff's Department who gives details on the police investigation of the murder-suicide, attorney Anne Bremner who is representing Chuck and Judy Cox, and close friends of the Powells.
20/20 (9 p.m., ABC/Ch. 4): What would drive a man to set his house on fire, murdering his two sons and killing himself - and could it have all been prevented?
ABC News Anchor Chris Cuomo takes viewers inside the Powell family tragedy with a complete, up-to-date report with exclusive details on the events leading up to Sunday's tragedy, and the fateful decisions by authorities and investigators which preceded the disaster. Cuomo explores the lingering questions in the case - did Josh kill his wife, Susan, back in 2009? If so, where is she? And is Josh's father, Steve Powell, the key to the case?
Dateline (9 p.m., NBC/Ch. 5): Keith Morrison goes back to Utah to report on the horrific developments of Josh Powell's murder-suicide that took place last Sunday.
A story "Dateline" has been reporting on since the disappearance of his wife, Susan Powell, two years ago, Morrison talks to the children's grandparents, Charles and Judy Cox, and Josh's sister and brother-in-law,Jennifer and Kirk Graves. Viewers will also see the last in-depth interview with Josh Powell.
I cannot begin to imagine what family members must be going through. It's difficult to say what I would do in their place.
I'm pretty sure I wouldn't go on "Dr. Phil," however.
Elsewhere on Friday ...
A Gifted Man (7 p.m., CBS/Ch. 2): A woman takes the clinic staff hostage.
Who Do You Think You Are? (7 p.m., NBC/Ch. 5): Marisa Tomei learns her family history.
Women's college gymnastics (7 p.m., BYUtv): Denver at BYU
CSI: NY (8 p.m., CBS/Ch. 2): Turns out two seemingly unrelated murders are connected.
Michael Feinstein's American Songbook (8 p.m., PBS/Ch. 7): Michael finds an unpublished song by composer Jerry Herman.
Fringe (8 p.m., Fox/Ch. 13): Olivia, Peter and Walter are unable to escape a town.
Supernatural (8 p.m., CW/Ch. 30): Sam is forced to confront a childhood fear.
NBA (8:30 p.m., ESPN and ROOT): Oklahoma City Thunder at Utah Jazz
Merlin (8 and 10 p.m., Syfy): Merlin falls into Morgana's hands.
Blue Bloods (9 p.m., CBS/Ch. 2): Frank investigates a rumor about a priest.
Spartacus (11 p.m., Starz): Spartacus has to deal with a schism within his ranks after they learn what happened to Naevia.
Elsewhere on Saturday ...
Men's college basketball: Utah at Arizona (noon, ROOT/FSN); Pepperdine at BYU (4 p.m., BYUtv)
Smash (7 p.m., NBC/Ch. 5): If you missed the outstanding premiere of this show, NBC gives you another chance to see it.
America's Most Wanted: Crimes of Passion Special Edition (7 p.m., Fox/Ch. 13): Two hours of criminal profiles.
An Idiot Abroad: The Bucket List (8, 9 and 11 p.m., Science): Karl goes whale watching in Alaska.
Saturday Night Live (10:30 p.m., Ch. 30): Zooey Deschanel hosts; Karmin performs.
Elsewhere on Sunday ...
54th Annual Grammy Awards (7 p.m., CBS/Ch. 2): LL Cool J hosts the ceremonies, live from the Staples Center in Los Angeles. (Tape delayed)
Once Upon a Time (7 p.m., ABC/Ch. 4): Mr. Gold's house is robbed.
The Simpsons (7 p.m., Fox.Ch. 13): Lisa falls for an intellectual (Michael Cera).
The Walking Dead (7, 9 and 10:30 p.m., AMC): In the first new episode since November, Rick and the others try to pick up the pieces after their horrifying discovery.
NBA (7:30 p.m., ESPN and ROOT): Utah Jazz at Memphis Grizzlies
Napoleon Dynamite (7:30 p.m., Fox/Ch. 13): Deb publishes an interview with Pedro in an attempt to save the school paper.
Desperate Housewives (8 p.m., ABC/Ch. 4): Julie comes home, and she's six months pregnant.
Downton Abbey (8 p.m., PBS/Ch. 7): The Spanish flu strikes Downton Abbey.
Comic Book Men (8 p.m., AMC): In the debut of Kevin Smith's reality show set at his comic book store, the staff is challenged to a competition.
Pan Am (9:01 p.m., ABC/Ch. 4): Ginny follows Dean to Rome.
Luck (10 and 11 p.m., HBO): Ace meets with a talented whiz kid.
Shameless (10 p.m., Showtime): Grammy Gallagher gets out on a medical furlough and goes after a meth dealer who owes her money.
House of Lies (11 p.m., Showtime): Marty has to deal with his son's school, and the stripper reappears.
Californication (11:30 p.m., Showtime): Samurai Apocalypse wants Hank's help with a song.