© Shauna Darcy When Shauna Darcy first brought Ruby home, the plan was to have Ruby act as a service dog to help her with anxiety, depression and agoraphobia. Ruby was an incredible service dog and companion from the very beginning — and quickly showed Darcy just how far she would go to help her.

© Shauna Darcy “While she was training to be a service dog I noticed that she started picking up on changes in my heart rate and would act funny — for example, paw at me, try to get my attention, get on top of me, etc.,” Darcy told The Dodo.

Picking up on Ruby’s cues, Darcy went to the doctor and discovered she had health issues she hadn't known about, including a rare heart condition called vascular Ehlers-Danlos syndrome. Ruby had known something was wrong even before Darcy did, and her main focus as a service dog quickly switched to Darcy’s cardiac issues.

© Shauna Darcy Every day, Ruby helps her mom with things like monitoring her heart rate and blood pressure, helping her during panic attacks and retrieving emergency medications. She also carries groceries, picks up dropped items and gets things her mom can’t reach, and is trained in deep pressure therapy.

“When I pass out she gets on top of me and applies all her pressure on me and licks my hands and face until I come around,” Darcy said.

© Shauna Darcy Ruby is there for her mom every single day — even when she doesn’t realize she needs her.

Last week, when Ruby started alerting her mom that something was wrong, she had no idea why. At that point, Darcy was feeling fine, but decided to trust Ruby and call an ambulance anyway, just in case.

“It turns out my heart was going into atrial fibrillation,” Darcy said. “By the time the paramedics came, I was in pain and barely conscious.”

© Shauna Darcy As the paramedics rushed Darcy to the hospital, she realized that Ruby had saved her life that day.

While Darcy was in the hospital and the doctors worked to get her stable again, Ruby refused to leave her mom’s side. Even while Darcy was unconscious, Ruby lay in her hospital bed, pressed up against her, hoping her mom could sense she was there and that her presence would make her feel safe.

© Shauna Darcy During their stay at the hospital, so many people stopped by to meet Ruby. She’s always very popular whenever she and her mom are at the hospital and loves saying hi to everyone — but also makes sure that she’s never too far away from her mom. She loves her so much, and her mom loves her just as much right back.

© Shauna Darcy Without Ruby, Darcy’s life would be very different. Ruby helps her mom stay healthy and safe every single day, and her mom is so grateful for everything she’s done for her.

“I wouldn't be alive without her,” Darcy said.

You can follow Ruby and her mom on their Instagram account.