Babies -- especially royal ones -- have their own agendas.
Here's where you come in: We're asking Us Weekly readers to put their guestimation skills to the ultimate test. Predict the future monarch's birth date and weight, get them right, and you could score a 7-day Caribbean vacation on Princess Cruises' Royal Princess, christened by Kate.
Think you're up to the task? Click here to submit your best guesses.
* NO PURCHASE NECESSARY. Void where prohibited. Open to residents of the United States and Washington, D.C. (EXCLUDING RESIDENTS OF OVERSEAS MILITARY INSTALLATIONS, PUERTO RICO AND OTHER U.S. TERRITORIES), who are 18 years of age or older as of 6/26/2013. To enter, log on to usmagazine.com/guess-the-weight-and-date and follow the registration and entering directions. Grand prize winners: 1; ARV: $2,388. Runner-up winners: 20; ARV: $69.95. Odds of winning depend on the number of eligible entries received. Sweepstakes begins at 9:00 a.m. edt on 6/26/2013 and ends on 11:59:59 p.m. edt on 7/3/2013. Certain restrictions may apply. Complete Official Rules are available at usmagazine.com/guess-the-weight-and-date.
This article originally appeared on Usmagazine.com: Kate Middleton Baby: Guess the Royal Baby's Weight, Birth Date and You Could Win a Cruise!