TENCEL™ Baby Sleeper - Tiny Engineers

Cranes, dump trucks, excavators — and the animal operators running them.

Forbes named these the best baby pajamas in 2025. The sleeper is the workhorse of the under-layer.

Material. TENCEL™ Lyocell with spandex for stretch. The TENCEL™ is the wood-pulp fiber Lenzing produces in a closed-loop process — 99% of water and solvents recycled, OEKO-TEX Standard 100 certified. The spandex is for shoulder stretch when you're getting a sleepy baby's arms through at 7:30 p.m. Together they're softer than cotton, smoother than bamboo rayon, and they hold their hand through fifty wash cycles. The pajamas your baby still has at 18 months are TENCEL™.

The print. Light blue ground with construction vehicles (cranes, dump trucks, excavators) operated by elephants, dinosaurs, and cats, with traffic cones, warning signs, and dirt piles.

Construction. Footie sleeper — the foot is enclosed so the baby's feet stay warm. Fold-over cuffs at the hands for the first few months (covers the fingernails without mittens that fall off), then fold them back when the baby wants the hands free. 2-way zipper from the chin to the ankle, opening from the bottom for diaper changes. Tagless inside the neck. Reinforced seams at the shoulders and crotch — the stress points on a sleeper that gets pulled on and off twice a day.

Sleepers and sleep bags work together. The sleeper is the under-layer — it doesn't carry the warmth math on its own. Pair with a 1.0 TOG TENCEL™ Sleep Bag for a 69–75°F nursery, a 0.5 TOG muslin sleep bag for 75–81°F, or wear alone in a warm room above 75°F if the baby protests the sleep bag.

TENCEL™ vs bamboo pajamas. Bamboo pajamas feel softer at the store. TENCEL™ pajamas feel softer at month six. The difference is what happens between the third and tenth wash — bamboo rayon starts pilling at the elbows and inside the legs; TENCEL™ holds its surface. For a garment you wash three times a week, the longer fiber is the better value.

Sizing. 0–3M, 3–6M, 6–9M, 9–12M, 12–18M, 18–24M. Size to current measurement. A sleeper that's too long puts the foot of the suit past the actual foot, which is a trip hazard once the baby starts crawling.

Care. Machine wash cold, tumble dry low. Do not bleach. Do not iron printed areas. The fold-over cuffs are designed to be stretched and released a few thousand times without losing shape.

Safety & certification. AAP safe-sleep compliant. Tested to CPSC, CPSIA, and ASTM standards. Material certified to OEKO-TEX Standard 100. Loulou Lollipop is a Certified B Corporation.

Browse all bamboo baby pajamas & TENCEL™ sleepers.

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