Juliana Soong saw Lal's photo, found out who the girl in the picture was, and asked Data to promise her he'd never try to create another android ever again.
REALLY?! I don't remember that part in the episode. I'll have to rewatch the episode. If true, then that's a horrible thing for Julian to say to Data. Bad mom!
Data should've continued his attempts at "procreating". Even tho Data didn't find the error in Lal, he should've created another android and use different types of "parenting".