Her daughter reassured her mother that everything will be OK and that the bad guys would not win, KTRK reported.
Abigail had one dream for her life, to become a police officer. She told the police chief in Freeport, Texas, that’s her goal when she grows up.
Chief Ray Garivey and the Arias' have bonded since first meeting in December, KTRK reported.
"The chemo and radiation hasn't worked and basically the family is now leaving it in God's hands and praying for a miracle," Garivey told CNN.
"They are a lot stronger than I am," Garivey told KTRK, in tears.
He also wanted to make Abigail’s dream come true.
First he had a custom uniform made in her size.
Then, on Thursday, he swore her in as an official member of the police force.
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During the ceremony, she vowed to fight the "bad guys" until the cancer is gone from her body, the police department posted on its Facebook page.