The missing therapy dog of a 9/11 first responder showed up at her front door this morning.

Paulina Santos says her yellow Labrador, Rocky, had been spooked by fireworks Wednesday and ran off from her Yonkers yard. Rocky was not wearing his collar when he ran off.

In a happy update, Santos says Rocky showed up safe and sound at her door at 4 a.m. 

Santos got Rocky six years ago. He helps her work through the trauma she experienced as a nurse responding to the Sept. 11 attacks.

 Santos says she plans to have a welcome home party for Rocky.

"I was just overjoyed, over the moon, so so happy," she says.