Photographer Rebecca Leimbach always wanted a sibling for her daughter, but after years of in vitro fertilization before Harper came along, she knew it wasn't likely.

Then one day 4-year-old Harper stepped out of her playroom in a princess costume alongside Lola, the family's 7-year-old English bulldog. Lola was wearing a tutu and a tiara, and Leimbach realized that while Harper may not have a brother or sister, she already had a four-legged playmate.

"That’s when I realized, I’m not going to feel bad about not giving her a sibling," she told "Today." "Lola is filling a bit of that void."

She says Lola is almost always at Harper's side, and the bulldog doesn't seem to mind the costumes and jewelry the little girl dresses her in.

"She just goes about her business wearing whatever Harper puts on her. She's very tolerant."

Leimbach began photographing the playful pair, and the Internet can't get enough of Harper and her best friend.

Take a look at some of Leimbach's adorable photos below. For more photos, check out Leimbach's Facebook page.

Lola and Harper in tub

Lola and Harper hug

Lola and Harper eating

Lola and Harper in princess costume

Lola and Harper in woods

Lola and Harper pose for photo

Lola and Harper in tent

Lola and Harper with mustache

Lola and Harper hugging

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Laura Moss writes about a variety of topics with a focus on animals, science, language and culture. But she mostly writes about cats.

This little girl's best friend has 4 legs and rocks a tutu
Photographer Rebecca Leimbach captures adorable moments between her 4-year-old daughter and her favorite playmate, Lola the English bulldog.