The pair got engaged and were planning to marry in the same weekend, reported Us magazine.
"Kevin told her he was going to Vegas for a job, but he surprised her by proposing and (then plans on) marrying her while they are there. Victoria really wanted this for a long time so she's gotta be blown away. She's proven herself with him from day one," a source said.
The former backup dancer, 35, and Prince, 30, a former volleyball pro turned special education teacher, have been dating since 2008. They have a daughter, Jordan Kay, who celebrates her 2nd birthday next week.