Kate Spade's Family 'Still Grieving' After Her Death, Niece Rachel Brosnahan Says

The year that has passed for Kate Spade's family since her death last June has not been an easy one, niece Rachel Brosnahan says.

The Marvelous Mrs. Maisel star, who presented at the 73rd Annual Tony Awards on Sunday, told PEOPLE on the event's red carpet that her family is still grieving.

"I think my family and I, as you can expect, are still grieving very deeply," Brosnahan said. "We miss her very much and it's been a tough year but it's been really wonderful to have the support or Kate Spade as a company and work with Frances Valentine to help keep her spirit and her work alive."

Spade died on June 5, 2018, at 55. The fashion designer and businesswoman's death was ruled as a suicide.

Brosnahan was announced as the new face of Spade's luxury footwear and handbags collections, Frances Valentine, in January. She told PEOPLE she was hoping to honor her late aunt's legacy.

"In the wake of Katy's passing, my family and I were so overwhelmed and encouraged by the love and support we received from those who were touched by Katy's work, many of whom were strangers from around the world," she said at the time. "When you lose someone you love, you search for boundless ways to keep their memory alive. This felt like a way to do that through her beautiful creations and an opportunity to share them with all of those who her work meant so much to."

On the anniversary of Spade's death, her original fashion brand, Kate Spade New York, announced it had completed its $1 million pledge to support suicide prevention and mental health organizations.

"The Kate Spade New York Foundation announced it is donating $200,000 to The Jed Foundation (JED), which works to protect emotional health and prevent suicide in teens and young adults by partnering with schools and colleges to improve education and awareness programs," the brand said in a statement.

Spade's husband, Andy Spade, honored Spade's memory with an emotional tribute last week, revealing that he planted a Christmas tree for her outside his and daughter Frances Beatrix's new home.

"Dear Katy, this tree is for you," Andy's Instagram post began. "Bea and [I] are planting it outside of our big window to keep your magical spirit and energy close to us [every day]. It will bless our new home in California and radiate your essence 365 days a year. You were [illuminated] and we feel your presence wherever we go."

He explained that he wanted to thank his late wife for "all of the wonderful gifts you gave me over the years."

"For your beauty, intelligence and grace under pressure," he wrote. "For your boundless generosity, unflappable honesty and kindness to all living things. For your strength, courage and conviction to your ideals. For your belief in me and so many others. For your infectious laughter and sharp wit."

"There was never a dull moment with you," he added. "Through the peaks and valleys and alleyways we serpentined through together you were always there. We grew up together, helped raise one another yet vowed to retain our innocence as best we could. You taught me that modesty is always the best policy, to see the good in everyone and to stand up for the crazy and less fortunate."

"You hated hype and loved the humble. You called me out on my bullshit yet were non-judgmental," he continued. "You talked straight and let me know when I was was being cynical or sarcastic."

Andy went on to call his late wife "my best friend, my confidant, my partner in life, business and mischief. The ying to my yang and the zig to my zag."

"We played ping pong with ideas," he wrote. "You were and still are my Superwoman. I hope you know how many people you inspired through the example you set in the way you lived and the work you created."

"You were and still are my favorite poem. I can't tell you how grateful I am for all you have given me and so many others. May your bright, multicolored spirit shine down on us everyday." he concluded. "Heaven is lucky to have you but please know you are truly missed by us still here on earth."

If you or someone you know needs help, please call the National Suicide Prevention Lifeline at 1-800-273-TALK (8255).

Photo credit: Walter McBride / Contributor / Getty