We swear by these lightweight onesies by Grass&Air. Sometimes the big fleece-lined puddle suits can be a bit hot so it's very helpful to have something like this classic Navy puddle suit that acts as a waterproof barrier that you can layer up underneath. 

Waterproof puddlesuits keep kids dry thanks to the durable, waterproof nylon fabric. 

 Features:

• Durable, waterproof nylon fabric
• Taped waterproof seams
• Back waist elastic for a comfortable fit
• Elasticated stirrups
• Available in Baby Pink, Baby Blue and Navy