Congratulatory messages about the new royal baby have been pouring in from around the world, but leave it to some seasoned parents to keep things very real.
"We're absolutely thrilled ... I'm very pleased to welcome my own brother to the sleep-deprivation society that is parenting," the Duke of Cambridge said in a laughing message to Prince Harry and Meghan Markle following the birth of their son.
Kensington Palace tweeted a video of Prince William and Duchess Catherine's message Tuesday, the day after the baby boy arrived early in the morning, weighing seven pounds, three ounces.
And oh, bless. In a sea of "delighted" and "overjoyed" messages from various members of the royal and extended family, this sound-bite is a delightfully jaded reminder of what new parenthood actually entails. And William and Catherine have three young children, so they know. They know.
Remember when Wills fell asleep during an Anzac Day service a few days after little Louis was born? THEY KNOW.
WATCH: The truth about sleep after you have a baby. Story continues below.
The sleep deprivation is real. A few recent British studies have found that new parents can lose anywhere from 44 to 50 full nights of sleep in the first year of their child's life. The same studies found that new parents get an average of just around five hours of sleep a night over the course of a year.
And sleep deprivation can affect everything from your mood to your physical health to your relationships.
In welcoming Harry (and Meghan) to the "Sleep Deprivation Society" (sometimes also affectionately called the zombie club), Prince William is every parent who ever gleefully warned an unsuspecting couple that they'll never sleep again.
Which is ... not exactly helpful. But it is a right of any card-carrying member of the Sleep Deprivation Society. So, welcome, all the same!
The couple announced their newborn's arrival on their Instagram account Monday morning, just minutes after the palace announced Meghan Markle was in labour.
Mother and baby are both doing well, the palace said in another statement. In an impromptu press conference Monday afternoon, Harry told reporters he and Meghan are "absolutely thrilled," and that we'll likely learn the baby's name (and see his little face!) on Wednesday during a photo call.
Hopefully, Harry can stay awake for it.