Billy Joel Marks Daughter Della Rose's 6th Birthday: 'We Love You More Every Day and Year'

Billy Joel is glad to have daughter Della Rose around!

The "Uptown Girl" singer, 72, celebrated his daughter's birthday Thursday as she turned 6 years old. Joel shared a series of photos on Instagram that also featured daughter Remy Anne, 3½, whom he also shares with wife Alexis.

The music icon and the accomplished equestrian welcomed daughter Della in August 2015, one month after they tied the knot at his estate on Long Island in New York. Joel is also dad to singer-songwriter Alexa Ray Joel, 35, his daughter with ex-wife Christie Brinkley.

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"Happy 6th Birthday Della Rose! On your birthday it reminds us of how grateful we are to have you in our lives. You and your sister have been our quarantine entertainment," writes Joel. "There are no other people we would want to be stuck with at home!!! We love you more every day and year."

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In December, for Alexa Ray's birthday, Joel shared a sweet video of Della singing happy birthday wishes to their older sister.

"Happy Birthday to our big sister @alexarayjoel. You have been singing us lullabies since we were born," read the caption at the time, shared alongside throwback photos of Alexa holding her sister as a newborn. "We are so excited to finally get to sing to you on your birthday. We love you more than words can say!"