Simplify the following text for a Grade 7 native English-speaking person.
Original: They later merged into the Soliantu tribe ( a word created by competitors Kathy-Vavrick O'Brien and Rob `` Boston Rob '' Mariano which they intended to mean `` Sacred Allegiance to the Sun . '' )
Simplified: They later merged ( combined ) into one tribe . Kathy Vavrick-O ` Brien and Rob `` Boston Rob '' Mariano named the new tribe `` Soliantu '' , a name they made up that means `` Sacred Allegiance to the Sun '' .