Washington [US], June 20 (ANI): Actor Mark Ruffalo took to social media to celebrate a special milestone as his son, Keen, turned 23. Sharing a series of photos on Instagram, Ruffalo expressed pride in his son’s journey and achievements. The post included nostalgic snapshots of Keen from his toddler years, capturing moments of father-son bonding amidst nature. Ruffalo also shared a recent photo of the pair smiling together against a mosaic wall, highlighting Keen’s striking resemblance to his father with their matching long curly hair and infectious smiles. “Happy Birthday, Keen. Love you so m…