Within a year, he was acting and singing on Broadway -- landing roles such as Tiny Tim, Chip Potts and Gavroche -- before busting out in a big way with an original Christmas song in 2002.

The single led to him signing with Columbia Records, which also brought in his 2 older siblings ... to form a family group that's still going strong.

The group put out their debut album in 2006, but it wasn't a huge success until much later ... after their popularity skyrocketed on the Disney Channel.

Earlier this year, the group reunited after a 6-year hiatus ... just months after this handsome fella tied the knot with one of India's highest-paid and most popular celebrities.