eBay

Kate Mack navy blue and white two-piece swimsuit in size 12 months
Open-back ruffled top has stripes and polka dots and is trimmed with a white rosette
Bottoms are striped to match

All brands are unique, so be sure to check the measurements below before purchasing. I combine shipping, so please visit my store if you're looking for more!

Approximate measurements (done one side, laid flat):

Top, length from shoulder strap: 11"
Width under arms: 9.5"
Bottoms, width across waist: 8.5"