Katherine Schwarzenegger and Chris Pratt have had their baby.

The author and actress have had a child together, the former's brother Patrick Schwarzenegger revealed.

Patrick told ET the news. "They're doing great -- just got her a little gift," he said.

Patrick was carrying a package with a pink ribbon on it. It is unclear whether the gift was for Katherine or the newborn.

Neither Katherine Schwarzenegger nor Chris Pratt have made an official announcement on the birth. They also haven't revealed the name of the baby.

ET reported that Katherine's father, Arnold Schwarzenegger, mother, Maria Shriver, and siblings, Christina and Christopher, were photographed visiting her house.

They also said that Pratt’s car was spotted at St. John’s Hospital in Santa Monica, California, on Friday afternoon.

A source told PEOPLE (via EW) that the baby is a girl.

They report: "They knew they were having a girl and were thrilled about it. Kat had a good pregnancy and she is hoping for a quick recovery. So far, so good.

"She is going through all the first-time mom emotions. She is extremely happy, but a bit tired and overwhelmed. Chris keeps being amazing though. It's comforting for Kat that he is already a dad and understands how it is to have a newborn."

The source said that the new mom is "doing well" and spent the weekend at home with her husband and baby girl.

Katherine Schwarzenegger and Chris Pratt got married last June in an intimate ceremony in Montecito, California.

The child's grandmother, Maria Shriver, confirmed the pregnancy on Instagram in April.

Chris Pratt has a seven year old, Jack, from his previous marriage to Anna Faris. This is Katherine Schwarzenegger's first child.