The actress was accompanied by her mother at the Pretty Happy book launch hosted by Fabletics in Los Angeles on Tuesday. The mother-daughter duo posed for pictures together on the carpet, while Russell arrived a few hours later to show his support.
Hudson, 36, looked casually chic in a black-and-white animal-print maxi dress, while Hawn, 70, looked effortlessly stylish in a deep-blue tiered dress as they smiled in front of the cameras.
Hawn couldn't help but gush about how proud she is of everything Hudson has accomplished in her career and her ability to stay true to herself while living in the spotlight.
"I see Katie as someone who will continue to grow. What I'm loving is her love of what she's doing – she's inspiring people, which I think is really important," she told reporters. "It's one thing to be an actress, it's another thing to be able to go out and be an inspiration for others. Take off the coat of actress and show who you really are. I'm very proud of her for that. That's an important thing because it's who you are, not what you do."
Once inside, the family sipped on margaritas and mingled with fellow guests including Nicole Richie, Rachel Zoe and Molly Sims.
With her new lifestyle book, Pretty Happy: Healthy Ways to Love Your Body, Hudson is hoping to inspire others to look within when it comes to jump-starting their fitness goals and ultimately finding happiness.
"The book is really about connecting to the things that you want, the things that you need, the things to make you happy – the things when life happens and is rough and kicks you off your feet, that you always know and understand and connect to the things that will motivate you," she told PEOPLE at the event. "Instead of sort of aiming for things that seem unattainable, to actually aim for things that feel more accessible."
Hudson said that while writing the book, she was surprised with how much she ended up learning about herself.
"There's two sides to me," she said. "There's this sort of business side and there's the fast-moving like, 'let's get everything going' side, but then there's my creative side that, like, to just lock myself in a room and get weird. That's just the reality of my life."
Reporting by CHRISTINA DUGAN