Casey Affleck Missed Brother Ben Affleck's Wedding Celebration Due to 'Parental Obligations'

Eric Charbonneau/Invision/AP

Not all of the Afflecks could be in attendance at this weekend's big wedding celebration weekend.

A source tells PEOPLE that Casey Affleck missed the Georgia ceremony celebrating his brother Ben Affleck's nuptials with Jennifer Lopez on Saturday "unfortunately because of family, parental obligations at home."

Casey, 47, was previously spotted stepping out Friday with girlfriend Caylee Cowan after a visit to Affleck family favorite Dunkin' Donuts in Los Angeles. The younger Affleck was photographed again Saturday in L.A. He shares sons Indiana, 18, and 14-year-old Atticus with ex-wife Summer Phoenix.

RELATED: Jennifer Lopez and Ben Affleck Celebrate Wedding in Georgia Ceremony with Friends and Family

Saturday's ceremony was still full of love with such stars in attendance as Ben's pal Matt Damon and wife Luciana Barroso, Clerks auteur Kevin Smith and wife Jennifer, as well as Clerks star Jason Mewes and wife Jordan Monsanto. Top Hollywood talent agent Patrick Whitesell and his wife, model/actress Pia Miller, were also in attendance.

For more on Jennifer Lopez and Ben Affleck's wedding celebration, listen below to our daily podcast PEOPLE Every Day.

A source told PEOPLE Friday that Affleck, 50, and Lopez, 53, "have an extraordinary weekend of celebrations planned," including "a pre-wedding party, a ceremony and ... lots of fun lined up," after the couple got married last month in Las Vegas.

Rich Fury/WireImage Ben Affleck and Jennifer Lopez

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According to the source, Lopez "is ecstatic" about the plans, and their "kids will be part of the celebrations too. It will be a beautiful weekend."

After they originally dated from 2002 to 2004, Affleck and Lopez rekindled their romance last year and announced their engagement in April.

The couple tied the knot at A Little White Wedding Chapel in Vegas during intimate midnight nuptials last month. A source told PEOPLE: "The Las Vegas ceremony was perfect. They both loved it. It was private and low-key. That's all they asked for."

RELATED VIDEO: Jennifer Lopez and Ben Affleck 'Clearly in Love' Ahead of Wedding Party in Ga., Says Spa Owner

They later jetted off to Paris for a romantic getaway, where they were photographed canoodling around the City of Love and celebrating Lopez's birthday, before continuing their jaunt around Europe.