Jennifer Garner and John Miller are secretly engaged, according to a source.

Garner, 52, and Miller, 46, have been together for six years already. Although the two prefer to keep their romance low-key, there has been a huge development in their relationship that they have been allegedly keeping among themselves for two years now -- their engagement.

An unnamed insider told Life & Style that the couple is "seriously in love." The actress and the businessman are reportedly in a place where they are "comfortable going out in public more than ever" because they are ready to tie the knot amid their secret two-year engagement.

Garner and Miller were spotted holding hands in Los Angeles on April 27. In the photos obtained by the Daily Mail, they looked carefree and were all smiles while holding hands and walking. They also shared a laugh while enjoying the stroll in Santa Monica, California, and appeared unbothered.

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A second source claimed that the CEO of Cali Group proposed to Garner when she celebrated her 50th birthday two years ago. The "Yes Day" actress didn't disappoint Miller because she reportedly said "Yes" to his proposal.

"John spent a long time making Jen an engagement ring and gave it to her two years ago, around April 2022, which is when she turned 50," the second tipster claimed.

Enstarz could not independently verify the engagement claims.

Jennifer Garner
Jennifer Garner attends the premiere of Netflix's "Family Switch" at AMC The Grove 14 on November 29, 2023 in Los Angeles, California.
(Photo : Frazer Harrison/Getty Images)

A report from OK! magazine in September 2022 also suggested that Garner and Miller were already engaged. The outlet claimed that the proposal happened in April 2022, shortly after her 50th birthday.

"Ben and J.Lo's nuptials have nothing to do with Jen and John's plans," an anonymous source said about the engagement as it was reported after her ex-husband Ben Affleck reconciled and tied the knot with Jennifer Lopez.

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Jennifer Garner
US actress Jennifer Garner arrives to the Daily Front Row Fashion LA Awards 2024 at The Beverly Hills Hotel in Beverly Hills, California on April 28, 2024.
(Photo : MICHAEL TRAN/AFP via Getty Images)

The source said Garner and Miller have "already decided they want a long-term future together" even before Affleck and Lopez's summer weddings. The "Gone Girl" actor and "Let's Get Loud" singer eloped in Las Vegas in July 2022 and married again in front of their friends and family a month later in his ranch in Georgia.

Garner was previously married to Scott Foley (2000 - 2004) and Affleck (2005 - 2018). She shares three kids with the "Batman" actor -- Violet, 18, Seraphina (now known as Fin), 15, and Samuel, 12.

Jennifer Garner and Ben Affleck
Actor Ben Affleck and actress Jennifer Garner pose during the 16th annual Critics' Choice Movie Awards at the Hollywood Palladium on January 14, 2011 in Los Angeles, California.
(Photo : Christopher Polk/Getty Images for VH1)

Garner and Affleck split in 2015 and finalized their divorce in 2018.

The source is hopeful that the "Elektra" actress has already found her forever in her rumored fiancé.

"They are perfect for each other," Life & Style's first insider added. "John really is her other half. She's told friends, 'I've never known love like this!'"

Jennifer Garner and Ben Affleck
Glenn Close (L), Ben Affleck (C) and Jennifer Garner arrive at the 2014 Vanity Fair Oscar Party on March 2, 2014 in West Hollywood, California.
(Photo : ADRIAN SANCHEZ-GONZALEZ/AFP via Getty Images)