Taylor Swift and her then-teenage boyfriend, Conor Kennedy, reportedly crashed Liam Kerr and Kyle Kennedy's wedding in August 2011. Though Swift's rep denied the claims, other guests, including Kathie Lee, said that Swift wasn't invited and that she and her hot high schooler never even RSVPed to the event, which they then refused to leave. Perhaps to karmically make up for the faux pas, in 2014, Swift "crashed" a fan's bridal shower -- but was more than welcome there, taking selfies with guests, delivering a barrage of gifts and generally being adorable.
INF Photo; Instagram.com/genagabrielle