No, the second sentence is not possible. These are possible (with various meanings): He helped (to) carry the box. He helped her (to) carry the box.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
TasmanTiger=> He helped the box carried . (?)No, it's wrong.
TasmanTiger 'Help + something + pp' is accepted grammatically?But carried is not a Prepositional Phrase, so you probably mean something else. (?)