Carrie Underwood is celebrating her son’s birthday.

The music superstar honoured Isaiah’s 6th birthday with a “Power Rangers” themed bash.

“Today, we celebrate Isaiah…because today, he is 6 whole years old! Isaiah, you are kind, funny, smart, the best big brother, a lover of cuddles and crafts and you have the biggest heart and the best imagination,” Underwood, who shares Isaiah with husband Mike Fisher, wrote.

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Adding, “You love to make people feel good and you especially love to make them laugh! God has given you so many gifts and every day, I thank Him that I get to be your mom! I love you, Monkey.”

Underwood added a second sweet photo of him hugging her.

Underwood and Fisher are also parents to Jacob, who turned 2-years-old last month.

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“We longed for you. We prayed for you. We walked a long, hard road in order to one day hold you,” Underwood wrote, referring to the three miscarriages she suffered before his birth.