Showbiz
According to E! Online, Reinhardt recently popped the question to the Simple Life star, although they decided not to go public with the news.
However, rumours of wedding bells for the couple were fuelled last month when Hilton revealed that she had been considering marriage.
The 28-year-old also hinted of her engagement during a recent acceptance speech at the Hearts for Hope benefit in Los Angeles, where she remarked: "I'd like to thank my future sister-in-law Casey Reinhardt."
A source said: "At one point, Paris reached for Doug's mum's huge wedding ring. She looked like she was in awe."
In December, Hilton staged a fake wedding with America's Got Talent judge Piers Morgan as part of a segment on his show Piers Morgan On... Las Vegas.
Related Stories
Ten Things About...
Ten Things About... Ridley ScottWe find out ten fast facts about the English producer and director.
Interviews
'ANTM' Laura LaFrate interviewThe runner-up speaks with Digital Spy about the contest and the other models.
Fashion & Beauty
Duchess of Cambridge's memorable momentsFlick through a gallery of Kate Middleton's stand-out public appearances.
Celeb Birthdays
Celebrity Birthdays: Clarkson, Tatum, moreFind out which famous faces will celebrate birthdays over the coming seven days.
