Simon Cowell proposed to Lauren Silverman on Christmas Eve after nearly 18 years of dating

Simon Cowell’s brother, Tony, is opening up about the America’s Got Talent judge’s recent engagement to longtime love Lauren Silverman.

In a recent column in the U.K.’s Best magazine, Tony said when he first heard the news from Silverman, he “immediately” thought of he and Simon’s late mother Julie, who died in 2015.

“She would have been overjoyed with the news, and it’s sad to think she is not here to see her son finally tie the knot,” he wrote. “She always wanted him to settle down with a family. I picture her looking down and saying, ‘and about time, Simon!’ “

Tony went on to share that he’s “not surprised” that the engaged couple, who share 7-year-old son Eric, have decided to wed after nearly 18 years together.

Simon Cowell and mom Julie. Alan Davidson/Shutterstock

“Since having his son, Eric, with Lauren, Simon has completely changed his life and, for the first time, he appears to be happy and content,” Tony wrote.

He added that he thinks Simon’s back injury in August 2020 “was the catalyst” for the American Idol alum’s proposal.

“He began to think about his future, and who to share it with,” Tony said. “I am very fond of Lauren; she is both a caring mum and a loyal companion to Simon. She is constantly reaching out to all our family; and was incredibly supportive to all of us following our mum’s death in 2015.”

Last week, PEOPLE confirmed that Cowell, 62, proposed to Silverman on Christmas Eve in Barbados, where they first met. A source later said the couple was meant to be together, calling them “soulmates.”

“They have fun together, as well as being each other’s rock,” the source told PEOPLE. “They are both passionate [about one another], but really do bring out the very best in each other. As a family, they all have such an incredible bond.”

Simon Cowell & Lauren Silverman. getty

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The source also noted that Cowell and Silverman, who have been dating since 2004, decided to get engaged now after recent events shifted their perspective on life.

“A lot of things have happened in the last few years and just like for everyone else in the world, these things have all been a reminder about what is precious to them,” the source explained.

​​Read the full Tony Cowell column in Best magazine, on sale Tuesday.