So, my team's levels are screwed up. Any suggestions on how I can get em all the same level again?

Account A (pally/main) - level 29
Account B (mage/alt) - level 29
Account C (mage/alt) - level 28
Account D (mage/alt) - level 29
Account E (priest/alt) - level 28

A referred B
B referred C
C referred D
D referred E

Shouldn't it let me grant levels to C and E or what? Or anyone got any suggestions on getting them even again? Because the next quest area starts at level 29 and I want them all to be even to start at the same time