Bruce Willis is “so sweet” with his granddaughter. The ‘Die Hard’ actor has retreated from the public eye after being diagnosed with frontotemporal dementia (FTD) but his daughter Rumer Willis has told fans he is doing “good” and she loves seeing him interact with her 13-month-old little girl Louetta. Appearing on ‘Today’, Rumer said of her dad: “He’s so good. I actually got to see him right before I came out [to New York]. “And Lou is just starting to walk a little bit, and she was walking over to him, and it was so sweet. “It’s so nice because I feel like my dad is just like – he’s a girl da…