We SHELLebrated our little mermaid turning 4 with a big under the sea party! She is obsessed with mermaids, so I wasn’t surprised at all by her request for a mermaid theme! She doesn’t particularly like The Little Mermaid movie, so we stuck with a more traditional mermaid vibe with lots of different colors of blues, purples, pinks, and pops of iridescent materials. It was such a fun (and chaotic) party.
You can read through about the decor, what we ate, and what we did, and shop all links at the bottom of the post!
Under The Sea Decor
Since we had to be inside for her party, I focused most of my energy on turning our main floor into an under the sea world! With green crepe paper and painters tape, I created seaweed around the walls, and cut out little bubbles. It was a cheap option and took about 20 minutes to do, but the impact was huge!
For the food/cake area, I created a balloon arch. There are tons of tutorials on youtube, and I even have one saved to my Party Highlight on Instagram. This looks like SUCH a daunting task, but I promise the hardest part is just filling the balloons. I used command strips and yarn to tie the whole thing together, and attach it to the wall.
You can find a tutorial here on how I did the little banners and the painted backdrop. I am a big fan of DIY projects for parties, because you can really customize it to your theme — and if it’s not perfect, you’re the only one who is going to notice – I promise!
For the treat bags, we fell in love with these adorable seashell bags. Adaline picked these amazing hair clips with a long, colorful hair extension for each one, that everyone got a kick out of. We also added mermaid stickers, and these fun multi-colored pens to each!
What We Ate
We had the party catered by Jimmy John’s – this is our typical party go-to. We just get a ton of 1/3 sandwiches, and people help themselves. I added a little pizzaz with some mermaid cupcake toppers as food picks.
I made the cake and cupcakes myself. I have a Cakes 2 Highlight saved on Instagram, where you can see the whole process. I did a simple watercolor technique that is actually really easy – just frost the cake white, pop it in the fridge for an hour, and then add little dollops of frosting around the cake. I didn’t really have an order or a pattern. Then, take a bench scraper, and smooth it out. The result is this pretty marbled, watercolor look that was perfect for our under the sea party. It’s easy to build, and add more colors, and this method is SUPER forgiving, too.
Addy had requested a “pink and blue and purple vanilla cake with cotton candy” — and that’s what she got!
What We Did
We had a few, fun activities planned to keep the kiddos occupied throughout the party.
Adaline specifically requested slime – actually, mermaid slime. Since mixing slime around a bunch of 3-5 year olds sounded like too much unneeded stress, I opted for this slime kit. Peyton and her friend ran the slime table. The kit came with a few fun “mix-ins” but I also ordered these fun seashell sequins and some beads that looked like pearls for the kids to add into their slime.
This actually occupied the kids for about 20 minutes – which I think deserves mentioning!!
When I asked Adaline what she wanted to eat for her birthday, she said she wanted to decorate cookies. I told her she had already requested cake, cupcakes, and cotton candy, so having cookies out might be a bit much (talk about a sugar high). She looked sad, so I offered up the idea of decorating cookies for an activity at her party, and she was SO into it. I found a shop on etsy that offers DIY kits for this. It was PERFECT.
The shop owner sent a ton of pre-made mermaid cookies, enough frosting for the kids to cover the cookies and themselves, and matching sprinkles. It was messy, chaotic, and SO much fun!
I’m glad I snapped the photos of the table set up – because we ended up staying at the slime table for this part, and it looked a lot less “Pinterest” and a lot more like The Purge.
Ah, every kid’s favorite part – right? Again, it was absolute chaos. Wrapping paper and tissue paper were everywhere!
Addy’s favorite gifts were her new, cozy mermaid blanket and her calculator. Yes. My 4 year old has an appreciation for office supplies!
All in all, the party was such a blast. We are still finding beads on the floor from the slime craft, but it was so worth it! You only turn 4 once 🙂 Happiest birthday, Addy!!
Addy’s Dress c/o
Decorative Fishing Net
Mermaid Photo-Op Cardboard Stand
Slime Bead Mix-ins
Slime Sequin Mix-ins
DIY Cookie Kit
Kid’s Table (legit we use this ALL the time!)
Floor Mat c/o
Balloons for Garland
Felt Coral Shapes
Shell Bowl (from London’s Pirate party! I knew we would use it again, haha!)
Shell Favor Bags
Pens for Favors
Stickers for Favors
Hair Clips for Favors
Everything Needed for Banner and Backdrop Linked Here
Cake Decorating Supplies All Linked Here
If I missed a link on something you’re looking for, please let me know! And if you attempt any of our DIYs, please tag us, so we can see!!