Big brother duty!

The images marked the first time Ryder posted about Rani since his famous mom welcomed the newborn on Oct. 2 with boyfriendDanny Fujikawa, 32. Ryder and Rani are also siblings to 7-year-old Bingham Hawn, whose father is Muse frontman Matt Bellamy, 40.

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Goldie’s Love In For Kids - Arrivals

Kate Hudson and son Ryder

Also on Monday, Fujikawa’s stepsister and Hudson’s longtime friendErin Fostershared cute photos of Rani on Instagram.

“When I was 19 my mom started dating a man named Ron. He came into our lives and made my mom happy for the first time in a very long time. He became a staple of unconditional love in my life that I needed. His 3 sons became family to us,” Foster captioned two photos of her mother Rebecca Dyer — who was married to David Foster from 1982-86 — and Ron Fujikawa as well as two photos of Rani.

“Meanwhile, Sara’s best friend from high school, Kate, was a part of our family over the 11 years they were together. Ron got sick and passed away 5 years ago and Kate was there every day supporting us,” Foster continued. “Then one night out of the blue Kate looked at one of Ron’s sons differently. They fell in love and now they have a daughter named after Ronnie, who brought them together. She helps it all make sense now Rani Rose Fujikawa.”

Erin Foster/Instagram

erin-foster-rani-rose

Erin Foster

“We have decided to name our daughter Rani (pronounced Ronnie) after her grandfather, Ron Fujikawa. Ron was the most special man who we all miss dearly. To name her after him is an honor,” Hudson explained. Fujikawa’s father died in October 2012.

source: people.com