CHICAGO -- The political action committee that is largely funded by the Ricketts family is about to run some attack ads targeting Republican presidential candidate Donald Trump.
Last month, Trump tweeted that the Ricketts should be careful about spending money against him and that they had a lot to hide.
Marlene Ricketts' family owns the Chicago Cubs. She donated $3 million to "Our Principles PAC."
The group is running an ad in Illinois about Trump University, which closed in 2010.
The ad brings about the lawsuits and other challenges the institution faced.
The New York attorney general is seeking restitution and damages for more than five thousand students.
Trump's attorney says the case is politically motivated.
Our Principles PAC has also accused Trump of not being a true conservative and using illegal immigrants for his building projects.
Trump's tweet about the Ricketts prompted Cubs Chairman Tom Ricketts to tell reporters, "It's a little surreal when Donald Trump threatens your mom."