That does not appear to be the case.

Spouse and kids (all GE members) all applied for NEXUS same date and all got conditional approval 10.5 weeks (on the same date). My kids are elementary school age so it's not like there's much background to check against.

Years ago when kids were applying for GE (one was an infant and the other a toddler), it took three weeks for conditional approval which was similar processing time for an adult GE applicant. Both kids were born in US.

Seems to me lowest risk applicants still take the same amount of time as adult.