Sen. Ted Cruz (R-Tex.) has said he will remain neutral in GOP primaries against Senate incumbents, but his dad is getting involved on behalf of a key House primary challenger.

Rafael Cruz, who might be more outspoken than his son on conservative causes, is backing activist Katrina Pierson, a primary challenger to Rep. Pete Sessions (R-Tex.).

From the Dallas Morning News:

On Monday, Cruz, the father of Sen. Ted Cruz, endorsed the Garland Republican in her bid to beat incumbent Pete Sessions in the March primary for the 32nd Congressional District seat.

“She’s a strict constitutionalist. She’s a strong conservative and she wants to do what’s right,” Cruz said at a Dallas fundraiser for Pierson.

Ted Cruz, whom Pierson supported for Senate against Lt. Gov. David Dewhurst, has not made an endorsement in the race.

The endorsement by Cruz's father should help Pierson, who endorsed Cruz's 2012 Senate bid, gather attention as she wages an uphill battle to unseat Sessions.

The tea party group FreedomWorks has also backed Pierson, but she raised a modest $36,500 in her first quarter as a candidate.

Cruz made news a couple months ago when video surfaced of a 2012 event at which he said he wanted to send President Obama "back to Kenya" -- a reference to claims that Obama wasn't born in the United States.