The phrase "champion sleeper" means someone who is really good at sleeping or who can sleep very well.
Sentences with «champion sleeper»
Some babies outgrow the newborn stage and become champion sleepers right out of the gate. (mattressadvisor.com)
A mom writes in for help with her previously champion sleeper who can now take up to 2 hours falling asleep on his own in his big kid bed. (alphamom.com)
A three - and - a-half-month old champion sleeper is now waking up every two hours during the night. (alphamom.com)