River Phoenixs sisterRain Phoenixpaid a touching tribute to the late actor on what would have been his 54th birthday.

Were all worth millions of planets and stars and galaxies and universes.

Riverdiedon Oct. 31, 1993, at the age of 23, from a drug overdose.

A side-by-side of Rain Phoenix and River Phoenix

Rain Phoenix and River PhoenixPhoto by Paul Archuleta/Getty Images / Photo by Robin Platzer/Getty Images

Happy birthday most beautiful one, he wrote.

Rock band Garbage wrote, He was a beautiful angel .

Too good for this world.

(L-R) River Phoenix and Kiefer Sutherland in ‘Stand by Me’