Chris Jackson / 1 / 12
Chris Jackson / 1 / 12

Sibling love. Prince William and Duchess Kate need not worry about any kind of sibling rivalry among their children, because their eldest kid was every bit as enthused about a sister as the rest of the world.

"George was very excited to meet his sister," a source told Us Weekly of they couple's firstborn prince.

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William brought his little mini-me to the Lindo Wing of St. Mary's Hospital in London shortly after Princess Charlotte Elizabeth Diana was born.

"George was aware that he would soon have a new brother or sister and has been excited throughout the pregnancy," the source said. "He might have been a little shy around the new baby, but I heard everything went well. He's great around other children. He's a very curious boy."

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George, of course, is one of the millions and millions of people excited for the birth of the child, who's now 4th in line for the British throne. The Palace even sent out a statement of gratitude a day after Charlotte was born.

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"The Palace was inundated by flowers and gifts from around the world, many from members of the public and others from important figures and officials they have met over the years," the source said.

The couple is now "ready for the challenge" of raising two children.

"They are a lot more calm this time," the source said. "I remember when George was brought back after he was born and they were so nervous. But the second time they feel relaxed and are able to take in and enjoy these first moments at home with the baby."