The appealing idea
People who care for dogs often organise life around another living being: food, exercise, health, safety and consistency. Those routines can create useful conversations about responsibility and lifestyle.
What research supports
Recent research suggests that pets can influence human mood and emotional expression, while studies of dog-human bonds show that many owners experience dogs as family or close companions. That supports the importance of dog compatibility in a relationship; it does not establish that all dog owners are better partners.
What remains unknowable
Some irresponsible people own dogs. Some wonderfully kind people cannot own one. Look at how somebody behaves over time: respect, reliability, boundaries, care and the ability to handle frustration.
The useful dating question
Ask how the person shares responsibility, what a normal weekend looks like, how they handle travel and what they have learned from caring for an animal. The answers matter more than the photograph.