Kendall and Kylie Jenner have paid heart-warming tributes to Caitlyn Jenner on Father's Day.

The sisters arrived in LA yesterday to be with Caitlyn to mark Father's Day and posted touching message on Instagram.

Kendall, 19, explained that Caitlyn's 'soul' had always been her 'daddy'.

"My whole life this soul was my dad and just because your appearance is different now doesn't you were any less of a father to me my entire life," she wrote.

"Happy Father's Day to the person who raised me, and taught me everything I know, my hero."

17-year-old Kylie posted a flashback image with a loving message writing "'Happy Father's Day my little light of sunshine."

Quoting Caitlyn she added: "You can still call me dad, Kylie. No matter what I'm always going to be your father. That's never going to change."

Kylie had posted a message the day before saying: "Gotta make it home in time for Father's Day."

Khloe Kardashian posted a throwback picture of her late father Robert Kardashian posing with the Olympic hero adding: "Thank you Lord for blessing me with not one phenomenal father but I was lucky enough to have two. Happy Father's Day!!!'"

Caitlyn unveiled her new identity as a woman on the cover of Vanity Fair earlier this month.

The Jenner-Kardashian clan took to Twitter to celebrate her courageous announcement that she would live her life as a woman.

It was revealed earlier this month that she still lets her children call her 'dad' as the family adjust to her transition.

A source previously told People: "[Caitlyn] spoke to each of the kids separately and told them to take their time in getting used to this. She would prefer not to be called 'Bruce,' but told the kids that they could still call her 'Dad,' at least for now."

Caitlyn Jenner recently gave a glimpse into her new social life as she shared a photo from 'girl's nights' on social media.

All of Jenner's children are expected to accompany her to the ESPY Awards on 15 June when she will make her red carpet debut.

The reality TV star will be honoured with the Arthur Ashe Courage Award at the event – an accolade presented to those whose contributions transcend sport. Past recipients of the award include one of the first openly gay NFL players Michael Sam, boxing great Muhammad Ali, and politician and philanthropist, Nelson Mandela.