Question about John Lennon?

What was the name of the song he wrote for his son Julian?

Paul wrote "Hey Jude" in reference to John's son, Julian.

"Beautiful Boy" was written for Sean.

Beautiful Boy. Hey Jude was written by Paul

"Good Night" on the White Album was written by John for Julian although sung by Ringo.

Lloyd is correct about the other two songs.

"Hey Jude" was written as "Hey Jules" but was changed by Paul because "Hey Jude" was easier to sing.

I think its called "Good Night"