Babies under six months should not wear sunscreen, which leaves clothing and shade as the only real options. Even after six months, the American Academy of Pediatrics recommends keeping little ones in protective clothing whenever possible, with sunscreen as the second layer of defense, not the first.

Sun safe clothing is one of those things that quietly does a lot of work. Here is what to look for, and which Pehr pieces have become summer staples for the families we hear from.

What UPF 50+ actually means

UPF, or Ultraviolet Protection Factor, measures how much UV radiation a fabric blocks. A UPF 50+ rating means the fabric blocks at least 98 percent of UV rays. Critically, the best UPF protection comes from the density and weave of the fabric itself, not a chemical treatment that washes out over time.

All of our swimwear achieves its UPF 50+ rating through fabric density alone, which means the protection lasts the life of the garment.

Look for these features

• Long sleeves and longer hems. More coverage means less exposed skin, full stop.

• High necklines or zip fronts with guards. The chest and upper back are common spots for redness on babies.

• Wide brim hats. The face, ears, and back of the neck get more sun than people realize.

• Quick dry, breathable fabric. A protective layer is only useful if your child will keep it on.

Pieces we reach for

Swim Long Sleeve One-Piece. Full coverage in a soft seersucker knit. The zip front and large head opening make it actually easy to get on a wiggly baby.

Swim Long Sleeve Ruffle One-Piece. The same UPF 50+ protection with a little frill. Fully lined.

Swim Rash Guard and Short set. A two piece option for toddlers who want more freedom of movement, with baby sizes featuring a bloomer bottom that fits over a swim diaper.

Seersucker Bucket Hat. A wide brim that shades the face and ears, in a fabric that breathes on hot days.

A note on sustainability

Our swim fabric is made from recycled polyester and nylon, which lowers the environmental impact of pieces that are already going to last for many seasons. Sun protection that is good for them, and a little better for the planet they will inherit.

Pair these with shade and good timing — the sun is strongest between 10 a.m. and 4 p.m. — and you've given your little one the best possible defense.