The No Doubt star's firstborn took to Instagram to post a sweet throwback photo of himself as a toddler holding hands with his model sibling, and wrote alongside it: "Happy birthday @daisylowe. Love you."
Daisy is Gavin Rossdale's oldest child, and has a close relationship with the Bush singer, as well as his other sons, Zuma and Apollo.
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Prior to the pandemic, Daisy - whose mother is model Pearl Lowe - often went to see her family in the United States, but has been unable to visit them over the past year due to the coronavirus restrictions.
Gavin and Daisy's relationship has never been stronger, but the father-daughter duo have faced their challenges over the years.
Gwen Stefani and Gavin Rossdale's son Kingston paid tribute to sister Daisy Lowe
After Pearl gave birth to Daisy, Gavin was made godfather, and at the time it was believed that the model was the daughter of the fashion designer's ex-boyfriend, Bronner Handwerger.
When Daisy was 14, she found out that neither her mother nor Bronner shared her O-type blood, which was when she asked for a paternity test to be taken.
Gavin Rossdale with his four children
While Daisy and Gavin are close, Pearl lost the musician as a friend when the DNA test results were revealed. Talking to Easy Living magazine in a previous interview, the mother-of-four explained: "While Daisy and I are close, things haven’t always been easy. It was a bit hairy for six months when I told her I suspected her father was the musician Gavin Rossdale.
"Gavin told me if Daisy, then 14, had a DNA test, he’d never speak to me again and he's kept his word. I lost him as a friend, but Daisy has a relationship with him, which is great."
Daisy Lowe with youngest brother Apollo
While Gavin is relatively private about his family life, he previously opened up about spending time with Daisy while in London back in 2017.
He told The Daily Star: "I have four children, Daisy who is here and doing her own thing. But I also have three young children and wherever they are I am compelled to be, they need me like tea needs milk."
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