I got these for DD1 last year for our vacation:
https://www.knixteen.com/products/pe...40254722113584
And they worked out very nicely. I would say we didn't severely test it (haha) but DD2 was on her period on a lighter flow day and there was no leaking. We still made sure to use a dark towel juuuust in case. They fit her really nicely and had great coverage, and the quality was good. We went by the hip measurements for the size chart, and it worked out perfectly. We also got her the matching bikini top and she wore that under her rash guard:
https://www.knixteen.com/products/do...40258564227120
Order early!!! They took a while to get here because they were coming from Canada!