Kids Long Sleeve Rash Guard

I struggle finding the right star rating for this rash guard because I generally find Primary clothing so great, but this one fell short. My 5 yo LOVES the colors and the feel of the fabric, but there are two issues: (1) the knit of the fabric catches fine sand that is impossible to get out. While functionally it's fine, visually (depending on the color of the sand) the shirt looks stained/ mildewy. I thought that I messed up leaving it in the wet bag too long, but then I realized that it was fine sand granules embedded into the fabric. (2) After a summer's worth of swim classes, the fabric has degraded/ thinned out around the neck and shoulder, and not in the expected areas typically in contact with the pool wall. I was hoping that it would last more than one season, so it didn't quite meet my expectations.