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DIY Infant Mermaid Halloween Costume

*** Check out our post here for more cute and unique baby boy costumes****

Yes, I am the kind of parent who really LOVES to coordinate my kids Halloween costumes.  I can totally see us being the family that all dresses up together someday! Today I am sharing the Halloween costume I used last year when my little girl was a baby.

 Infant Mermaid Halloween Costume by Since baby girl was just an infant, last year big brother got to choose his costume first. He wanted to be a pirate so I decided to make the little one a mermaid for Halloween! This ended up to be perfect since I knew a proper mermaid costume would restrict her legs.  Since she was only 3 months she didn’t need to move her legs so I got to get her all dressed up for Halloween just how I wanted! You will be surprised how easy this stunning infant mermaid costume is! To make the tail you will use the exact method we explain here in our How To Make a Tutu Tutorial.  The only difference is that instead of making this on elastic, I used a crochet knit headband.  Then  you will make the length much longer so that it will cover their legs and have enough left over to gather for the tail  Infant Mermaid Halloween Costume by I love using the headband because it gives a pop of color, fits right to baby’s body and it stretches for comfort. You simply cut enough tulle to tie knots within most all of the holes on the bottom row of the headband.  I layered sparkly blue, sparkly green, and regular teal together.  The length should be the length of baby from waist to toe, plus about 8 inches. Once you loop all of the tulle, fluff the tulle then measure down to the bottom of where the toes would be and use a thin rubber band to gather the tulle and create the tail effect.  I used a small piece of tulle to wrap around the rubber band to cover it. Isn’t the glitter tulle super fun?!  Glitter did get EVERYWHERE, but it was worth it to get that beautiful shimmer on her tutu.  Infant Mermaid Halloween Costume by To make the sea shell top, simply get a second head band and glue the seashells to it!  So easy!! We wore this costume just as in the picture while it was warm out and then when it cooled down we added a long sleeved onesie and pants underneath. We are still deciding on our Halloween costumes for this year!  I would love to hear what you are dressing your kids up as in the comments below!

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  1. says

    Holy cow! Most adorable costume EVER!! Have you linked this at any of the handmade Halloween costume contests on line? There are a few, and there are prizes- go get a prize!!

  2. Courtney Davis says

    Ok so I am going attempt making all of my children’s Halloween costumes this year and LOVE this one for my newborn. However, I am new to this, could you tell me how much tulle I will need of each of the three colors. Just need to know what to tell the lady when she asks how many feet/yards I need. :) Thanks in advance.

    • says

      Hi Courtney- I am so glad you like the costume! It is one of my all time favorites! They sell the tulle at Hobby Lobby and JoAnns and prob most other craft stores on spools that are 25 yards for around $5 (you can get a great deal with a coupon!). I think I used about 3 full spools on this project. Let me know if you have other questions.

  3. Kate says

    This is MUCH easier then the way that I was trying to do this!!! SOOO glad I decided to search one last time before I got started. I already sewed up a tail so might just stuff the tulle in where I was going to attach it to the “skirt” (that I was still trying to get to come together right lol). Best thing Hobby Lobby has the tulle on a spool 40%off this week!

  4. renie says

    Oh my goodness! I just made this and it is too cute. I was so not prepared for all this glitter though haha. Think I’ll be finding glitter all over my house for a few weeks.

  5. Kate says

    That’s what I get for not reading ALL the instructions!! Thought I could just figure out the tutu part on my own & didn’t want to take the whole 5min to read the other post (I’m one of those lol) and spent ALL day looping tool through the headband and hand sewing it in place one by one! O M G!! It really wouldn’t have taken nearly as long if my 3yr old didn’t need something every 10sec and the baby always decided to eat when I just got in the swing of it. Grrrrr………she is the slowest eater on the planet too. We got alot of compliments in our test run at the pumpkin patch yesterday BUT how do you keep them from kicking their feet through? I can’t put her in the wagon because she doesn’t like how it’s so bumpy. So while I’m holding her, her feet pop right out? I was thinking of making a lil sack to put in the skirt?

    • says

      I know! I am the same way. I am glad you like the tutorial though! They definitely can kick out their legs. My daughter was pretty tiny when I made this for her so she didn’t do it too much but I think a sack underneath would be a great idea. Or if it is cold where you are you might could find a white sleep sack and use that under the costume instead of a onesie. Thanks so much for stopping my and leaving a comment!

  6. Kelly Pickard says

    I absolutely love this mermaid idea and am going to attempt to make it for my newborns halloween parade at school this week. I couldn’t quite grasp how you were able to knot the tulle onto the headband, can you explain? Do I just loop it through and make a hand knot? :)

    • says

      Thank you so much Kelly! Did you click through to the tutu tutorial I referenced above? There is a pretty detailed explanation there with step by step pics. Check it out and let me know if you still have questions. I would love to help.

      • Kelly Pickard says

        I made this last night for my 3month old little girl and I absolutely love it!!!! Thank you so much! I wasn’t quite understanding but the lady at hobby lobby walked me through and it was super easy!!!!’ I plan on using this skill many more times and you have a new fan in me!! Xo

        • says

          Thank you Kelly! That makes me SO happy! I love that you were able to make a special costume for your little one! We look forward to having you here!

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