A dispute between two political families escalated Tuesday as Donald Trump Jr. canceled plans to raise money for the eldest son of former Florida Gov. Jeb Bush.

Donald Trump Jr. decided to withdraw from a fundraiser for Texas land commissioner George P. Bush in New York City next week after Jeb Bush criticized President Donald Trump’s policy of separating immigrant children from their families at the border, according to two people with direct knowledge of the situation. They spoke on condition of anonymity to discuss private conversations.

“Children shouldn’t be used as a negotiating tool,” Jeb Bush, the brother of former President George W. Bush, and a Trump opponent in the 2016 Republican presidential primary, wrote on Twitter Monday. Bush called on Trump to “end this heartless policy.”

That was too much for 40-year-old Trump Jr., who had been supportive of 42-year-old George P. Bush’s political aspirations, but had warned him repeatedly to get Bush’s dad to back off his father. Bad blood has lingered between the two patriarchs since the 2016 campaign.

In March, Jeb Bush poked Trump during an appearance at Yale University, saying Bush goes home every day to children “who actually love me.” Trump Jr. responded publicly on Twitter: “I love my father very much.” And privately, according to the sources, he expressed his displeasure to George P. Bush.

The sons had maintained a decent relationship despite the tension between their fathers, the sources said. The younger Bush was the only member of the Bush family to endorse Trump in 2016.

His aunt, former first lady Laura Bush, also lashed out at the Trump administration immigration policies on Monday. In a Washington Post op-ed, she said the Republican president’s policy was “cruel” and “breaks my heart.”

The younger Trump was scheduled to headline a fundraiser on Monday for the younger Bush, who is facing re-election this fall. Bush was elected to his first term as the commissioner of the Texas General Land Office in 2014, a statewide office that could open the door to run another state or federal office in the future.

A spokesman for George P. Bush did not comment on the cancellation, which was first reported by Axios.

(AP)