Schlossberg’s father Edwin and siblings Jack and Rose were also spotted among the gathering of loved ones.
Numerous members of the famously private Kennedy family were seen spilling out on to Park Ave after the service, including cousins Maria Shriver and Kerry Kennedy.
Former President Joe Biden and comedian David Letterman were also in attendance, as well as Carolina Herrera, who designed Schlossberg’s wedding gown in 2017.
Schlossberg died on December 30 weeks after she shared her acute myeloid leukaemia diagnosis in an essay for The New Yorker.
An environmental journalist, she graduated from Yale in 2012 with a Bachelor of Arts in history.
She described her shock when doctors told her the news in “A Battle With My Blood”, which was released on the 62nd anniversary of JFK’s assassination.
“I did not – could not – believe that they were talking about me,” she wrote.
“I had swum a mile in the pool the day before, nine months pregnant. I wasn’t sick. I didn’t feel sick. I was actually one of the healthiest people I knew.”
She praised husband George for his dedicated care for her during her illness, saying he “did everything for me that he possibly could”.
“He talked to all the doctors and insurance people that I didn’t want to talk to; he slept on the floor of the hospital; he didn’t get mad when I was raging on steroids and yelled at him that I did not like Schweppes ginger ale, only Canada Dry.
“I know that not everyone can be married to a doctor, but if you can, it’s a very good idea.
“He is perfect, and I feel so cheated and so sad that I don’t get to keep living the wonderful life I had with this kind, funny, handsome genius I managed to find.”
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