"I just feel like she's my best friend and we really get along well," Robert says of Susan. "And she also just calls me on everything. And she's multi-tasking squared. She's doing this and she's doing that. She's reading a script. She's pinning her hair. And it just blows my mind how capable she is in functioning in life. And she has a great sense of humor and she's a little bit crazy, too, because she's sitting right here next to me. We're getting married."