Amy Schumer publicly defended her cousin, Senator Chuck Schumer, against Donald Trump, after the U.S. president taunted the New York Senator for displaying human emotion and empathy.

Senator Schumer held back tears when he spoke out against Trump's unconstitutional immigration ban -- which bars refugees and citizens from seven Muslim-majority countries from entering the U.S. -- on Sunday (January 29), eliciting a response from Trump in which he accused the Senator of faking his reaction.

Then, unable to ever let anything go, Trump referred to the Senator as "Fake Tears Chuck Schumer" in a tweet, two days later.

This spurred the Trainwreck actress to respond to Trump's taunts in a lengthy Instagram post, where she defended her politician cousin, writing, "I know chuck Schumer and HE CANNOT act trust me. He can barely smile on cue. He can't help but be transparent and genuine. He was hurt for those people and all the people facing such unconstitutional injustice."

Schumer -- who was one of several celebrities to appear at the Women's March protests last month -- then warned her followers against complacency, urging them to take action to oppose Trump and his forthcoming policies.

"We can't get burnt out or overwhelmed and distracted. We need to stay focused and organized," she wrote. "Tell your friends who say 'I'm just not political' that that doesn't cut it anymore. We need people alert and fighting for each other's rights. Tell your sheltered friends to wake up and help.

"If you live somewhere where you've never even met a Muslim person and it feels like this doesn't really affect you. It does," the caption continued. "A Muslim ban is so unconstitutional and cruel. They are good, hard working people and a refugee from the countries he isn't letting people in from have never committed any acts of terrorism on US soil. Never. We need to fight this now and together. Call congress. Call the senate. We need to wake up and rise up together. People need our help."

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