"Rumer knew when she was pregnant that this was a special time, not just for her, but for her dad, too," the source explained, noting Bruce "lit up when he held little Lou."
"It was such an emotional moment — so many feelings. Rumer was in tears," the source gushed of the special family moment. "There wasn’t a dry eye in the room. It was beautiful and bittersweet."
This sweet meeting comes only two months after his previous aphasia diagnosis was updated to frontotemporal dementia in February — both conditions that caused the actor to make the decision to press pause on his career.
"Unfortunately, challenges with communication are just one symptom of the disease Bruce faces," his current wife, Emma Heming Willis, shared at the time. "While this is painful, it is a relief to finally have a clear diagnosis."
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Despite the Die Hard actor's ongoing health woes, the source revealed that getting to meet the newborn is a light in the midst of darkness.
"Bruce’s health battle has been very difficult for everyone, but meeting his first grandchild brought the entire family even that much closer," the source added. "Rumer couldn't wait — she brought the baby to her dad right away."
"It felt as if Bruce had received a boost of energy," the source continued. "He didn't say this, but it's like his granddaughter gave him a reason to fight even harder. The power of pure love in that moment was very intense. Everyone felt it."
"He fell in love with her instantly," the source noted. "She's like an angel from heaven."
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The source spoke with In Touch about Bruce meeting his granddaughter.