But insiders suggested that the 44-year-old actor regretted that he and wife, Catherine Schneiderman, hadn’t started their own family while Bert was alive.
“Matthew sees how happy his sister is and really wants a baby,” the source tells.
“It would be lovely for Patti, who adores her grandkids, but having another one from Matthew would be the icing on the cake.
"If Matthew was a dad, it would be tinged with sadness though, given how close he was with Bert at the end, and that he will never meet that child."
WATCH: Matthew Newton talks about his troubled past
The 44-year-old has been notoriously private about his life since packing up and leaving Australia in 2012, but it was there that he met his now-wife, whose father was the former New York Attorney-General, Eric Schneiderman.
Matthew and Catherine, 28, married in a secret ceremony four years ago, but none of his family reportedly attended the service and it had never officially been announced that they'd tied the knot.
However, during Bert's funeral service, the Dean of St Patrick's Cathedral, Werner Utri, referred to Catherine Schneiderman as Matthew's wife, ultimately putting rumours of a breakup to rest.
Matthew and Catherine got engaged in October 2016, and the following year, a source close to the Newtons claimed to New Idea the couple exchanged 'I dos' in a private ceremony at the home of Catherine's mother in New York.
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