Hi there!

I'm so sorry to hear your kiddo got some blisters =( In most cases, blisters are caused by fit issues or shoes being a little stiff.

If the shoes are worn, we unfortunately cannot accept them for a return or exchange but we have some suggestions to help.

As we do for ourselves when wearing any new shoe, we want to give time to break in the shoe. Wearing them for short periods of time at first can make or break any shoe as we know. I would also note that the Kaiden are waterproof so they are a firmer shoe compared to some of our other styles.

We also suggest making sure the size is correct. If its too big or too small, sometimes blister's can be seen. I suggest measuring in inches and then adding about 1/4-1/2 inch for growing room. If the shoe is too small, or maybe just for a better fit, you can remove the insole for extra room in the shoe.

We also offer the Growth Spurt Guarantee for the cases that the shoes are worn but are too small.
The Growth Spurt Guarantee helps families who had kids outgrow their shoes that were purchased from our website in the past 30 days. We offer a discount of 50% off, plus shipping for one of the next sizes up from the outgrown shoe size if the order was placed with us within the last month.

If the shoes just aren't a good match for your kiddo, we would suggest checking out replae.co where our customers sell our shoes in new and used conditions.

We hope that helps and feel free to reach out with more questions.
Warmest regards,
Plae - Customer Care