"With immense sadness, the Holy Father has seen the images of the father and his baby daughter who drowned in the Rio Grande River while trying to cross the border between Mexico and the United States," the Vatican's interim spokesman, Alessandro Gisotti, said in a statement.
"The pope is profoundly saddened by their death, and is praying for them and for all migrants who have lost their lives while seeking to flee war and misery," he said.
Photographs, which have been widely published around the world, show the bodies of a father and his 23-month-old daughter face down along the banks of the Rio Grande near Matamoros, Mexico, across the river from Brownsville, Texas.
Earlier, in off-the-cuff comments during his weekly audience in St. Peter's Square, the pontiff complimented the people of Mexico for being "so welcoming to migrants. God bless you." A group of Mexicans attending the audience cheered and waved a Mexican flag in response.
Francis has frequently been vocal in his support of Mexico's efforts to help migrants and critical of the U.S. for blocking them at the border. During a visit to the U.S.-Mexico border in 2016, he criticized then-presidential candidate Donald Trump, suggesting that anyone who wanted to build a wall along the border was "not a Christian."
In April, the pontiff donated $500,000 to help migrants in Mexico, offering assistance to local projects that provide food, lodging and basic necessities.
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