Rebecca Rosen, the author of the book What the Dead Have Taught Me About Living Well, said that lighting mishaps are common signs that someone is trying to connect. "It's easy for spirits to manipulate electricity and cross wires, so to speak, because both spirits and electricity are forms of energy that vibrate at a high frequency and are highly charged," wrote Rosen for Oprah.com. "Look for lights flickering in the house, lightbulbs blowing out or disturbance with television sets, radios, appliances and computers."

When my husband and I got married at sunset last fall, I was caught off-guard when the string of lights along the brick wall right behind us started blinking on and off. My frustration with the lights quickly turned to joy when I realized that maybe my dad was in attendance after all.

Have you ever noticed circles of light in photographs you've taken? While some might chalk them up to lighting issues or camera malfunctions, many mediums believe these orbs are signs from the spirit world.

Natalia Kuna, an Australia-based psychic medium, wrote on her blog, "Orbs are said to be captured images of spirit beings or energy consciousness. They can be anything from loved ones in spirit, to fairies, angels, archangels and other light beings." In other words, don't delete or toss photos if you spot an orb or two. Those are the most special!

Music is one of the most emotionally-powerful ways a spirit can communicate with you. Sue Nicholson, a well-known psychic medium and spiritual counselor, wrote on her site that hearing familiar or sentimental songs are not something to overlook. "Often people will hear a piece of music that reminds them of someone that has passed over. You may turn on the radio and hear a piece of music that was played at their funeral, it’s just them saying hello!" Additionally, if you've ever been spooked by the radio turning on by itself or a kid's toy spontaneously bursting into song, that's a sign as well.

For me, the song that I always associate with my dad is "Come On Eileen." Yes, it's embarrassing to tear up when that tune comes on, but I know it's him.

Remember how you could always see Haley Joel Osment's breath in the scariest ghost scenes from Sixth Sense? Turns out, many psychic mediums believe that unexplained changes in temperature can signal that a spirit is around.

Amanda Linette Meder, psychic medium, writer, and teacher, explains on her site, "It’s actually temperature in either direction - not necessarily cold-only changes. Any change in the energetic properties of the space - through temperature or pressure - is often a sign that energy (any energy, not just a ghostly energy) has shifted in the space, moving either into the space around you or out of the space around you." In Meder's experience, loved ones will often cause increases in temperature, so pay attention to those random hot flashes.

As a self-proclaimed "crazy" dog lady, I make no secret of the fact that I think dogs are superior to humans in many ways. Apparently, many psychic mediums believe dogs may be more attuned to the spirit world, as well. If you've ever noticed your dogs barking at nothing, fixated on something you can't see, or acting out of the ordinary, there's a chance they could be sensing a spirit you're missing.

Karen Anderson, a professional animal communicator and psychic medium, told Chewy.com that dogs can absolutely see spirits. “Dogs can see the spirits with their eyes because they have the ability to see things that we can’t,” Anderson explained. “And they can hear things we can’t, so they can pick up the energy that way, too.” If you notice Fido acting off, you may have company. This is when I personally take a moment, slow down, and see if I notice any other signs or messages around me.

Have you ever had a thought, or even a command, pop into your head seemingly out of nowhere? Many mediums believe that these "telepathic" thoughts, or thoughts that don't seem to be your own, are messages from the spirit world. Higher Perspectives, a spirituality blog, describes the experience as, "having thoughts that don't feel like they're yours, almost like your internal monologue has been co-opted."

My mom experienced this phenomenon a couple of years ago, and she told me the story the following day. She was missing my dad particularly badly one night, and said internally, "I wish I could speak to you." Shortly after, she heard his voice in her head clear as day. "Go in the kitchen." My mom said she almost rolled her eyes, thinking to herself, "That's not exactly the message I was hoping for." She heard his voice again: "Don't ask me for a message just to ignore it." She reluctantly got out of bed and went downstairs into the kitchen, which was filled with gas. My brother had left the stove on while making a midnight snack. It turns out, my dad was looking out for my family even from afar.

Scent is a powerful connection to memory, and, according to mediums, it can be a connection to a loved one we've lost as well. Jodie Rimmer, a psychic medium and author of the website Sensing Angels, wrote, "We can often tell our passed loved ones are around us by smells like perfume, cigar/cigarette smoke, particular flowers, cooking, or any other familiar smell they had."

If you catch a whiff of that dish your late grandmother used to make or recognize your departed husband's cologne on the street, they're probably with you.

Whether you're a believer through and through or an unwavering skeptic, there is no escaping the grief that comes with losing someone we love. These signs can serve as messages that they're never really gone, as well as reminders to be grateful that you knew and loved them while you could.

This first-time mom wants to have a home birth, but is she ready? Watch how a doula supports a military mom who's determined to have a home birth in Episode One of Romper's Doula Diaries, Season Two, below. Visit Bustle Digital Group's YouTube page for the next three episodes, launching Mondays in December.