There's a specific kind of song that gets written between midnight and 4 AM, in a dim room, by a person who would trade everything they own for two more hours of sleep. It doesn't always sound like a lullaby. Sometimes it sounds like a pop ballad or a folk song or a Disney soundtrack. But the origin is the same: a parent holding a child, trying to make something beautiful out of exhaustion.

Some of these became massive hits. The audiences who loved them had no idea they were listening to a bedtime song.

"You'll Be in My Heart" -- Phil Collins

Before this was the Oscar-winning centerpiece of Disney's Tarzan soundtrack, Phil Collins wrote it for his daughter Lily. She was a baby, and he was trying to comfort her. The lyrics are essentially a father telling a child that he'll be there no matter what, which is also what Tarzan is about, which is why Disney wanted the song in the first place.

Collins has said in interviews that the melody came to him while he was holding Lily and tapping a rhythm on her back. The tapping became the percussion line. The studio version is polished and layered, built for radio. But the bones of it are a father patting his infant daughter's back at some unreasonable hour.

"Lullabye (Goodnight, My Angel)" -- Billy Joel

Billy Joel's daughter Alexa Ray was young when she asked him a question that no parent is ready for: "What happens when you die?" His answer was this song. It's about the idea that a parent's love persists even after they're gone, that it lives in the child's memory and dreams.

Joel has performed it live hundreds of times and still gets emotional. In a 2013 interview he said it was the most personal song he'd ever written. Alexa Ray, now in her 30s, has performed it herself.

"Forever Young" -- Bob Dylan

Dylan wrote this for his son Jakob (later the frontman of The Wallflowers). It appeared on the 1974 album Planet Waves, which Dylan recorded shortly after reconnecting with his family. The song is a series of wishes for a child: stay courageous, stay honest, be happy. Dylan being Dylan, he recorded two very different versions on the same album and couldn't decide which one he preferred.

The song has been covered and referenced so many times since then that most people have forgotten it started as a father singing to a specific kid. Rod Stewart's 1988 version charted higher than Dylan's original, which is the kind of thing that happens when you write a song so universal it stops belonging to you.

"Lovin' You" -- Minnie Riperton

This one has a detail most people miss. At the very end of the song, during the fade-out, Minnie Riperton whispers her daughter's name. That daughter is Maya Rudolph, the comedian and actress. Riperton and her husband, songwriter Richard Rudolph, wrote the song as a lullaby for their kids. It became a #1 hit in 1975.

Riperton's five-octave vocal range turned a simple lullaby into one of the most recognizable songs of the decade. The famous high-note section -- the part everyone tries and fails to replicate -- was just her singing to her children.

"Isn't She Lovely" -- Stevie Wonder

Stevie Wonder wrote this the day his daughter Aisha was born. He was so excited that he recorded it with the sound of her actual newborn cries mixed into the track. At over six minutes long, with a harmonica solo, it wasn't designed for radio. Wonder refused to release it as a single despite enormous demand from the label. To him it was a personal song, not a product. Radio stations played the album cut anyway.

Aisha Morris grew up to become a singer herself. She's performed the song live with her father.

"Mama Said" -- Lenny Kravitz

Kravitz wrote this for his daughter Zoe when she was three. He was going through a divorce from Lisa Bonet and struggling with how to be present for his kid while his personal life was falling apart. The song is about a mother's reassurance that everything will be alright. Kravitz has said it was as much about what he needed to hear as what he wanted Zoe to know.

Zoe Kravitz, now an actor and musician, has talked publicly about how the song shaped her understanding of her parents' relationship. A three-year-old doesn't understand divorce, but she can understand a song that says someone loves her.

What they have in common

Every one of these songs started the same way: a parent trying to say something to a child who was too young to understand words. Music filled the gap. You can't explain mortality to a toddler, but you can sing a melody that makes her feel safe. Divorce doesn't translate either, but a song that says "I'm not going anywhere" does.

Most of us aren't going to write a #1 hit for our kids. That's fine. The impulse is what matters -- wanting to give them something that captures how you feel about them, right now, while they're this small and the nights are this long.

Starry Songs turns that impulse into an actual lullaby, with your child's name in the lyrics, in about 60 seconds. Try it on the App Store.