"I've been waiting years for this"

Rebekah Brown's late brother Joshua was there in spirit

Her secretory carcinoma diagnosis accounts for only 0.15% of breast cancers and is "very treatable"

"I wanted to make the greatest love story that African-Americans had ever seen"

The song arrives one week before the release of the band's fifth studio album, 'Made in the A.M.'

There's even a photo of them together when they were toddlers