And in between beach dates and discovering the Greek island of Skiathos by boat, Kate found time to post a cute video of her two-year-old daughter Rani reciting the ABC, with the actress encouraging her by playing the song on the piano at the same time.
WATCH: Kate Hudson's daughter sings the ABC song
"And that, ladies and gentleman, is how to sing your ABC's #TeachEmYoung #HappyMusicDay," the actress captioned the 44-second clip.
Proud grandmother Goldie was one of the first to react, commenting: "I have no words only inordinate amounts of love #RAINROSEROCKS," followed by a red heart emoji.
Kate shares Rani with her partner Danny Fujikawa
Vanessa Bryant added: "She's so cute!" whilst Amanda Kloots said of her son: "Elvis loved watching this. I think we need to start a mommy band Kate!"
Goldie has an incredible relationship with her grandchildren and back in 2014 revealed that she was proud of how they were being raised by their parents, her son Oliver Hudson and daughter Kate.
"Kurt and I are so proud. They're mirroring a lot of the way they were raised, and that just shows you how important it is to raise your kids well, 'cause they will raise their kids well," she told TODAY in 2014.
Oliver shares three children, Wilder, Bhodi and Rio, with wife Erinn Bartlett, while Kate shares son Ryder with ex-husband Chris Robinson, son Bingham with ex-fiancé Matt Bellamy, and daughter Rani Rose with boyfriend Danny Fujikawa.
Goldie and Kurt are also parents to son Wyatt Russell, who welcomed his first child with wife Meredith Hagner earlier this year.