Ah, 25. The quarter century mark. What a wonderful age to be. Even more wonderful if your girlfriend is Jennifer Lopez and she's helping you celebrate.

That's the position Casper Smart was in last week, when his superstar boo gifted him with a customized white Dodge Ram truck and a birthday dinner.

"Jennifer had planned a fun day to celebrate Casper's birthday," a source told PEOPLE. "[She] knew that Casper really wanted a truck, and Casper was very excited about the generous gift. Casper was so excited about his new truck that he decided to drive it to dinner. She was smiling about Casper's excitement."