Since the children between Prince Nagaya and Imperial Princess Kibi were specially treated as the second princes (originally the third princes of Emperor Tenmu) by Empress Genmei, a maternal grandmother, there is also a possibility that Prince Nagaya was also specially treated.
長屋王と吉備内親王の間の子供達が外祖母にあたる元明天皇によって二世王の待遇（元来は天武天皇の三世王）を受けていることなどから長屋王に対しても特別待遇がされていた可能性もある。