Katherine Schwarzenegger and her younger sister Christina hit the tennis court in Brentwood

Katherine Schwarzenegger laughs in the parking lot as she and her younger sister Christina hit the tennis court in Brentwood

They are sisters who were once part of California‘s first family.

And Katherine and Christina Schwarzenegger looked to be in good spirits on Monday, when they were seen getting in a tennis match at a court in Brentwood, California.

Katherine, 31, and Christina, 29, dressed similarly in black sweatshirts and matching leggings. 

Laughing: Katherine Schwarzenegger looked to be in good spirits on Monday, when she was seen getting in a tennis match with her sister Christina at a court in Brentwood

Katherine’s top featured the words ‘For Days’ on the front.

The close sisters also both wore white tennis shoes with black ankle socks. 

They even twinned in similar black baseball caps and large sunshades.

Christina was seen with her hair in a top bun, while her elder sister kept her tresses back with a large white hair clip. 

Twinning: Katherine, 31, and Christina, 29, dressed similarly in black sweatshirts and matching leggings, as they handed off rackets

Twinning: Katherine, 31, and Christina, 29, dressed similarly in black sweatshirts and matching leggings, as they handed off rackets

A Georgetown University graduate, Christina added an extra layer with a quilted black vest, and a green T-shirt underneath.

The daughters of Arnold Schwarzenegger and Maria Shriver also made sure to mask up as Los Angeles County still remains one of the highest in the nation in terms of coronavirus cases. 

The sisters were seen handing off tennis rackets while Katherine shouldered a powder blue handbag. 

Masked up: A Georgetown University graduate, Christina (left) added an extra layer with a quilted black vest, and a green T-shirt underneath

Masked up: A Georgetown University graduate, Christina (left) added an extra layer with a quilted black vest, and a green T-shirt underneath

Last fall, the wife of Chris Pratt revealed that her sister Christina has become a ‘very involved auntie’ to her six-month-old daughter Lyla.

The Gift of Forgiveness author was talking about the Christmas tradition she does with her sister every year, and her hopes of passing it down to her daughter in the future.

‘I always traditionally do a sleepover with my sister the night before Christmas Eve. I’m hoping that that’s something that I can continue doing and bring [Lyla] along to do it, which will be fun,’ she told People Magazine

Last fall: The wife of Chris Pratt revealed that her sister Christina has become a 'very involved auntie' to her six-month-old daughter Lyla; Katherine seen recently on Instagram

Last fall: The wife of Chris Pratt revealed that her sister Christina has become a ‘very involved auntie’ to her six-month-old daughter Lyla; Katherine seen recently on Instagram

The family then gathers at mom Maria Shriver’s house for Christmas Day celebrations.

‘We spend Christmas with my whole family and we’re at my mom [Maria Shriver]’s house and my dad [Arnold Schwarzenegger] comes over and we all meet there and spend the whole day there. And we’re just together, which is my favorite time of the year,’ she added.

Katherine and her husband Chris Pratt welcomed baby Lyla, their first child together, in August 2020, more than a year after tying the knot in Montecito, California. 

Seen together on Instagram: Katherine and her husband Chris Pratt welcomed baby Lyla, their first child together, in August 2020, more than a year after tying the knot in Montecito

Seen together on Instagram: Katherine and her husband Chris Pratt welcomed baby Lyla, their first child together, in August 2020, more than a year after tying the knot in Montecito