Liam flew in from a festival gig in Germany, which had been cancelled on Friday (02Jun17) following a bomb threat, to perform three songs at One Love.
Bieber and Grande's manager, Scooter Braun, noted that the singer performed her first concert in Manchester exactly two years before.
Many people praised Morgan for apologizing and some expressed shock over his initial statements.
Grande said that she had met with the mother of 15-year-old victim Olivia Campbell-Hardy, who said she "wouldn't have wanted her to cry" but would have wanted her to "play all the hits". She appeared teary-eyed and emotional as she performed "Be Alright" and "Break Free".
She told the audience, "Manchester, we're gonna be all right".
All proceeds from the concert are going to the Red Cross' Manchester Emergency Fund, to help victims of the attack and their families.
Take That, who are from Manchester, followed Mumford. We love you, we're with you, all of us are with you.
Canadian man mows lawn with tornado behind him
Wessels later explained the tornado was not as close as it appeared to be in the photo and was moving away from their home at the time .
Less than 24 hours before the concert got underway, Britain was rocked by another terrorist attack, in central London, in which seven people were killed and 48 injured.
The mega-gig was broadcast live on TV stations in 50 countries around the world.
Twenty-two people were killed and more than 100 wounded when Salman Abedi detonated an explosive device in the Arena foyer as fans were departing.
Grande came back onstage to sing Fergie's verse on the Black Eyed Peas hit, "Where Is the Love?" along with the group.
They say the auto and knife rampage in London on Saturday did little to ease their worries.
"So that means that we had a totally different show planned and we had a rehearsal yesterday where we changed everything and this evening has been so light and so filled with fun and love and bright energy and I want to thank you for that".
Cyrus was one of several musicians to join Grande on stage for the benefit concert.