Keeping in mind this is where your child will (hopefully) be sleeping in long stretches, especially if the cot you’re buying converts into a toddler bed. Just like adults, babies need comfort and support to protect their growing bodies. Options include natural fibres, spring, foam and anti-allergy baby mattresses. Ensure no more than a 2cm gap surrounds your baby mattress once inside the cot. Always check your baby mattress is supported by the Sids and Kids organisation.