The 29-year-old skier spent Sunday hanging out with her man's 6-year-old daughter, Sam, as he competed in the Honda Classic in Palm Beach Gardens, Fla.
The blond beauty and little Sam stood among the crowd while watching Sam's dad make his way across the putting green. Sam looked adorable in a red polo shirt and black skirt, while Vonn sported a pink tee and pants. Sam stood close to Vonn, who kept her arms around Sam.
"Lindsay and Sam were seen laughing and joking around with one another," a source adds. "Lindsay and Sam at one point were holding hands and hugging. They were fooling around most of the time. They watched Tiger for three holes. They all seemed like a normal, happy family. They were all laughing and smiling, enjoying the day."
"Lindsay looked like she was having a great time and looked like a good mom, paying Sam lots of attention," the eyewitness said.
Meanwhile, Woods matched his daughter in black pants and a red polo shirt with a baseball cap.
Woods didn't have the best golf game on Sunday, despite the support of his girlfriend and daughter. He withdrew from the Classic after 13 holes due to back spasms that were causing him pain.
On Friday, Vonn was also seen looking over Woods' 5-year-old son, Charlie, while he played in the Honda Classic two days prior to their Sunday outing. Vonn, Sam and Charlie all matched in coordinating green polo shirts. Too cute.
Vonn and Woods have been dating since first getting together back in March 2013.