Inside: Sisters have a special brand of magic. Here are 18 things to do with your sister before you turn 18 to honor that sister magic. But if you're older than 18, it's not too late.

Nine years ago this month, I lost my sister. Too early. She would be turning 51 this month.

When I think of Lisa and the last few years when I could have spent more time with her, the regret sticks in my throat.

She left this world before my kids entered it. She never got to meet them, and I never got to ask for her advice on being a good mom.

She took me to my first professional baseball game. To my first pro basketball game, too. On my first roller coaster. I never took her to do something new she hadn't done before. Not even to a new restaurant.

She always gave me two birthday cards. A sweet, heartfelt card, and one to make me laugh. After I left home for college, I don't think I remembered to send her a single card.

Related: A Letter to My Sister About Sisterhood

The Things That Sisters Do

On the icy day that I was born, when the ambulance couldn't get to our home in time, 13-year-old Lisa was on the phone with 911. They told her what to do, and she did it. She was there from the very first second I entered this world.

She used to make us nachos in the microwave. The best freaking nachos. And I've never been able to get mine to turn out as good as hers.

When I was 13, she had me watch Nightmare on Elm Street. I wouldn't take a bath for years afterwards because I was afraid Freddy Krueger would come up through the drain. But she also let me watch Dirty Dancing before my mom would let me. And then a few months later when my mom decided I was old enough, I had to sit there and pretend it was my first time watching it.

Sisters have a special brand of magic, and now I see that same magic sparking between my girls.

Watching them grow up together fills my heart to the brim. Watching their sister magic – even when they're driving each other crazy – I can't help but smile.

But the regret. It sticks in my throat.

I wish I could go back in time and do all the things I never did with my big sister.

And so I made myself a promise. I will nurture this beautiful, sometimes volatile sister magic between my girls. I will set the stage for my girls to do all the things that sisters should do together.

Related: The Ultimate List of the Best Picture Books About Friendship

18 Things to Do With Your Sister Before You Turn 18

If you have daughters, look for opportunities to support and encourage these activities so your girls can deepen their bond of sisterhood.

And if you're an adult with a sister and you haven't checked off all these awesome sister-bonding activities quite yet, I promise you it's not too late.

  1. Stay up late in bed together, whispering made up stories to each other.
  2. Try out new hairstyles on each other. (As long as no scissors are involved.)
  3. Sneak the younger one into a movie she's technically too young for.
  4. Have a knock-down-drag-out fight over something stupid. Then apologize to each other, without anyone forcing you to.
  5. Admit your deepest, darkest fears to each other – whether she's afraid her nose is too big for her face or you're afraid you'll never understand chemistry.
  6. Borrow each other's clothes or jewelry.
  7. Do a 1000-piece puzzle together.
  8. Share inside jokes that no one else understands.
  9. Bake something together and get batter everywhere, even the ceiling.
  10. Hear a new song on the radio, fall in love with it, and go on an all-day binge listening to all that artist's music.
  11. Play a prank on your parents.
  12. Teach the younger one what to do if someone touches your body in a way you don't like.
  13. Give yourselves matching pedicures.
  14. Spend all day in your jammies watching your favorite movies.
  15. Ride a scary roller coaster together.
  16. Read out loud to each other.
  17. Go to each other's sports games, concerts, and plays.
  18. When she's fighting with her friends, listen and take her side – because she'll return the favor one day.
Before you go, get my FREE cheat sheet: 75 Positive Phrases Every Child Needs to Hear

Want More?

Read A Letter to My Sister About Sisterhood for more about the special brand of sister magic.

Your Turn

What ideas do you have for things to do with your sister? Share in a comment below!

18 Things to Do With Your Sister Before You Turn 18

I'm a mom of four, a Certified Parent Educator, and the author of Happy You, Happy Family. I believe if you want a loving parent-child relationship that will last into the teenage years and beyond, the time for nurturing that kind of relationship is now. The good news? All you need is 10 minutes a day. Start here »