Assertion: gene's child | /r/HasProperty | several tumors
Facets:
value: within the eye
type: LOCATION
value: often
type: TEMPORAL
Source sentences:
text: Children born with a mutation in the RB1 gene usually develop retinoblastoma in both eyes (known as bilateral retinoblastoma), and there are often several tumors within the eye (known as multifocal retinoblastoma).