When you have the same parents, but that is pretty much where the similarities end.

My children are complete opposites—eighteen months apart and entirely different little humans. My littlest is sensitive, anxious, shy and sweet. While my older is outgoing with a huge personality, likes to rough house, and will one day be the CEO of this universe. How is that possible? She will find a way, just wait and see.

They don’t even look alike.

Genetics are funny like that.

I see this in many families.

Sisters and brothers from the same parents are physically, emotionally and mentally different.

Take my sister and I. We are polar opposites. She has always been outgoing, a little rebellious, a free spirit, and could care less about what anyone thinks about her. While me: I was the boring rule follower, a Type A personality that wasn’t happy unless achieving and doing a million things, and am extremely sensitive and at a time cared way too much about what others thought. My parents would describe us as night and day, hot and cold, oil and water (you get the point). We always got along, both of us aren’t competitive, but we just never had coinciding interests.

A lot of the time, it’s like we are speaking different languages to each other (still), her in concerts and travels and me, in Beat Bugs, potty training, and breastmilk.

Because of this my parents to this day treat us differently and expect different things from us. I mean, they should, we are different people.

I have been realizing with myself that my expectations for my children are different already. This past week my 16-month-old was having tantrums, and it was very odd for me. Not because I haven't dealt with tantrums before, my almost-three-year-old is a pro tantrum thrower. It was just bizarre coming from my shy, easy-going, and sensitive daughter that hardly ever gives me a tough time.

I think that kids do pick up on parents’ beliefs about them, so I plan always to encourage and stay open-minded when they are figuring out who they are. I don’t want to put them in the boxes I already found myself doing in the above personality descriptions. Maybe my little one will surprise us all and turn into a little boss baby overnight.

Bottom-line: These two will have a profound role in shaping each other, and I am hell-bent on making it as positive as possible, just like my parents did for my sister and I. Also, my girls are different and I will encourage these differences and support them.

This post originally appeared on the author's Facebook . Her book Living FULL: Winning My Battle with Eating Disorder is available for preorder on amazon: https://amzn.to/2O4mJId