The pre-teen is getting ready to become a big sister once again, with mom Kourtney and stepdad Travis Barker expecting a baby son any day now.
Over at her dad's home, meanwhile, she's been taking care of another new arrival in the form of a puppy.
Scott took to Instagram at the start of the week to share a photo of their new four legged friend. "I got P a pup and I think I love her," he wrote in the caption, alongside an adorable picture of a tiny dog.
Penelope adores animals and is also the proud owner of her dog Honey, who she has had since 2017.
Honey is a Pomeranian and her twin, Sushi, belongs to Penelope's cousin, North West. The twin dogs featured in Keeping Up with the Kardashians in 2017, which focused on Kim Kardashian attempting to swap the dogs due to Sushi's barking.
In an episode back in December 2017, Kim said: "I swear [Honey] likes me better now, she's adjusted. Look how calm she is, you're not getting her back," after the swap took place.
Kourtney, who is also mom to sons Mason and Reign, replied: "This is not your dog! Do you even like dogs? You hate dogs! It's Penelope's! It's not yours."
Kourtney eventually traded the dogs back and returned Honey to her daughter. Kim wasn't so happy, saying in the confessional: "I mean, whatever, I guess she can have her dog back and I will just have to deal with Sushi's barking forever."
Penelope's new puppy's name has not been revealed, but Scott will no doubt share more updates of the cute addition to their family.
While Kourtney is part of an incredibly famous family, she is cautious not to share too much about her three young children on social media.
However, last week, the doting mom shared an insight into just how thoughtful her own daughter was, after sharing a picture of some flowers Penelope had given her while she was ill, which came with a note that read: ""I hope you feel better Mom. Love P."
Penelope and her siblings are no doubt looking forward to welcoming their new brother into their family. While Kourtney hasn't disclosed her pregnancy due date, she previously hinted that it was between October-December.
Fans have also been told that Kourtney and Travis are expecting a baby boy, after they held a gender reveal party in June.
The baby's name may also have been let slip by the couple too! A comment on a now-deleted photo from their baby shower read: "May Baby Rocky have... life filled with love." Meanwhile, in an interview with Complex earlier this year, Travis told his daughter Alabama that he loves the name Rocky 13.
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