The photo came days after Nicky Hilton Rothschild shared one of Lily-Grace off on her "first day of school," walking hand-in-hand with dad James Rothschild

Paris Hilton is reporting for “auntie” duty!

The heiress, 38, joined sister Nicky Hilton Rothschild‘s 3-year-old daughter Lily-Grace Victoria for a bonding session where the duo were captured on camera in front of a white shelf featuring an impressive collection of Funko Pop! toys, bunny figurines and more.

Lily-Grace — whose face is obscured, as in any photos her mother shares of her and her 20-month-old little sister Theodora “Teddy” Marilyn — is wearing a pink ballet outfit and pink hair bow in the cute Monday snapshot, petting Paris’ tiny black chihuahua, Diamond Baby.

“Auntie P 💘,” Nicky, 35, captioned the image — on which her big sister commented, “My love! 😍👑” and the siblings’ mom Kathy Hilton left several red heart emojis.

Nicky Hilton Paris
Credit: Nicky Hilton/Instagram. Inset: Charles Sykes/Bravo/NBCU Photo Bank via Getty

The photograph came days after the mother of two shared one of her older daughter embarking on her “first day of school,” sporting a pink bunny-face backpack as she walked hand-in-hand with dad James Rothschild.

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In a March 2018 interview with PEOPLE, Nicky opened up about her daughter’s bond with her aunt — and her major love for Paris’ pets.

“Lily-Grace gets excited when Aunt Paris comes over because she loves animals and Paris always has her dogs with her,” she added, explaining that the proud aunt flew in for the birth of Teddy. “Every time Paris is in New York, she makes a point to come visit the girls every day. It’s very sweet.”

The previous month, Paris told Entertainment Tonight that she was itching to become a mom herself, thanks to her adorable nieces.

“I have baby fever,” she revealed. “It gives me hope, because I know she has amazing genes. It runs in the family, so I’m not gonna have to worry.”

Oscar de la Renta show, Front Row, Fall Winter 2019, New York Fashion Week, USA - 12 Feb 2019
Paris Hilton (L) and Nicky Hilton Rothschild
| Credit: Swan Gallet/WWD/REX/Shutterstock

RELATED VIDEO: A Hilton Heir! Barron Hilton and Wife Tessa Expecting First Child

In the meantime, both Paris and Nicky will have a new little one to love on in just a few months.

Their younger brother, Barron Hilton, recently revealed exclusively to PEOPLE that he and his wife Tessa are expecting their first child together.

“The couple is radiating with joy,” their rep told PEOPLE last week.

Barron, 29, and Tessa, who will welcome their baby in the spring, conceived in St. Barts — the same place the two met three years ago and where they tied the knot on June 3, 2018.