Less than a day after debuting on The Today ShowKelly Clarkson and Hoda Kotb's "I've Loved You Since Forever" has hit No. 1 on iTunes.

The soft-toned lullaby was written in conjunction with Kotb's new children's book of the same name, which she penned in honor of her her one-year old daughter Haley Joy. I've Loved You Since Forever, a picture book, has been described as, "a celebratory and poetic testament to the timeless love felt between parent and child."

Kotb is a noted fan of Clarkson's. Back in 2016, she and the singer both choked up during her performance of Hamilton's "It's Quiet Uptown" on The Today show.

"There is one person I know who has a voice that is in a class by itself," Kotb explained on Thursday (March 8) while unveiling the song.

I've Loved You Since Forever is currently on sale. Each download or stream of the accompanying track will be donated to Helpusadopt.org, which assists young couples with the cost of adoption.

Watch the world premiere of the track below.

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