ALLEGAN, Mich.-- Two dogs living under the same roof have become inseparable according to their owners. Now the youngest of the two is what the owners are calling their hero for saving his sister.

Friday morning the dogs went outside to play like they do every day, and the oldest of the two, one and a half year-old Hunter, walked into a near deadly situation. Her younger sister, 6-month-old Bentley, was right by her side, to save her life before it was too late.

“It could have been really bad,” said Lisa Cassidy, “she wouldn't be here if it wasn't for Bentley.”

Hunter is still here, and able to play with her best friend and little sister, Bentley.

“They are buds. They are almost inseparable. If one goes outside without the other one they will sit there and bark,” said Tim Cassidy.

Hunter is usually the one to take care of Bentley like grooming, or snuggling together when they nap. Tim and Lisa say Hunter always has her eye on her little sis, but Friday their roles changed.

“I got up in the morning and the first thing we usually do is let the dogs outside. I opened up the door, and they raced outside to play,” said Tim.

Shortly after, Bentley was running back and forth from the pond in back of their house to Tim's office window, barking consistently and loudly. It finally caught his attention.

“Bentley was running back and forth in the yard by herself which was odd because they are always chasing each other. I didn’t see Hunter anywhere,” said Tim.

There was no Hunter in sight, finally Tim followed Bentley.

“All of a sudden Bentley stopped at the edge of the ice and was staring at her all I could see was her nose sticking out from under the ice,” said Tim.

Hunter had fallen through the ice, and was fighting to stay above water for 15 minutes. Tim jumped into action.

“I have a canoe so I dragged it across the yard, and got myself to the middle of the pond. Hunter c had just about had it. She had been out there for I don't know how long but she was out of gas,” said Tim.

Tim grabbed her just in time. He rushed her inside to get her warm. They swaddled her with blankets, and even took a blow dryer out to get her dry as fast as possible.

“Animals tell you something I’m glad Tim paid attention,” said Lisa Cassidy.

A relieved Lisa says they owe it all to Bentley.

“They have an incredible bond and she wasn't going to stop until Hunter was safe. They have each other's backs,” said Lisa.

The Cassidy’s say they try to keep the dogs away from the pond from now on, but now have an emergency plan in place if something like that was to happen again.