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Is Pippa Middleton going to be a mother soon? The sister of Kate Middleton and her husband James Matthews are believed to be expecting their first child after tying the knot in a lavish ceremony back in May.

According to Woman's Day, Pippa is currently two months pregnant. "Pippa always said she wanted to start a family as soon as she got married, and now her wish has come true," a source tells the website. "It's [still her] early days - and they have decided they don't want to know the sex of their baby until after it's born - but Pippa is convinced she is having a little girl."

The source further explains that being pregnant won't stop Pippa from working out at the gym. "She has seen other fit and healthy moms-to-be with a small, neat baby bump - and she's hoping to stay as active as possible right up until the baby is born," the source says.

Although Pippa wants to keep her body in shape, sometimes it's impossible for her to hit the gym because she suffers from morning sickness. "She has missed a few gym sessions and was due to go cycling with friends, which she had to cancel [due to morning sickness]. But it's not bad like Kate's was," the source dishes.

Prior to this, Kate was also believed to be pregnant as she was reportedly hospitalized in Marylebone, London. A source revealed that the mother-of-two even left Prince George and Princess Charlotte with her mother to be taken care of. Kate only stayed in the hospital for a night, but people speculated that she suffered from severe morning sickness since she was diagnosed with hyperemesis gravidarum when she was pregnant with George back in 2012.

The sisters were claimed to be wanting to have children at the same time. "Pippa and Kate are extremely close and have discussed how it would be fun to have children at the same time," an insider shared. "They've been looking at baby clothes online together!"