Children seem to be relatively delayed in their comprehension of the verbal "be"-passive in English, compared to their acquisition of other constructions of object-movement such as "wh"-questions and unaccusatives. Prior work has found that children's performance on these passives can be affected by the verb's lexical semantics. Through a meta-analysis of experimental studies assessing English-speaking children's age of acquisition for the verbal "be"-passive, we identify a developmental trajectory composed of five classes, where each class has a distinct lexical semantic profile. A Truth-Value Judgment (TVJ) Task assessing English-speaking children's comprehension of verbal be-passives supports this developmental trajectory. Together, the meta-analysis and TVJ study underscore the importance of lexical semantics for understanding the development of the English verbal "be"-passive.