*** (3 stars out of 5)
She introduces herself to Data: she was Doctor Soong's colleague and wife. Data's already met his father, brother, and grandfather, and now here's his mom. What's next for the foundling from the doomed planet? My votes are: hot sister and flying robot dogs... with capes.
Juliana never changed her name from O'Donnell to avoid her mother's wrath at a secret marriage to an old lunatic. She left Noonien in the jungles of Terlina, which Data reports as the place he died. The news affects her deeply. (Good thing Data doesn't mention Lore killed him, or how Data killed Lore. Could Aunt May's heart take it?)
When she hears about the loss of her grand-daughter Lal, she confesses that she and Noonien lost three prototypes before Lore. (Insert ominous sting music. In the context of the episode, 'lost' sounds like 'died', but later stories reveal it's more like 'lost' as in 'under couch cushions'.) Lore turned out cruel, and they had to de-activate him. She was against making Data, and was so terrified that #5 might turn out rotten that she forced Noonien to abandon him. She has since tearfully regretted her choice to give him up. (Just not enough to pick up a communicator or mail a letter.)
Data picks up on something strange: Juliana blinks in the same programmable randomization as all Soong-type androids. And in a cave-in, proof arrives when, like Astar, a robot, she can put her arm back on. She was programmed to believe she was the original Juliana, and her external form offers no clues otherwise. She emits life signs to fool scanners, VISORs, and apparently Betazoid empaths. She even has an aging program, like Data's. (It's one of the least popular apps at the app store.)
There's a holographic Soong in her brain. He explains the biological Juliana was injured during the Crystalline Entity attack, and near death by the time they got to Terlina III. He built his most sophisticated android yet and used synaptic scan to make a copy of Juliana's mind. It worked so well that she eventually got dissatisfied and left him. (Somehow he got this message into her brain after she left him? Must have a wireless update feature.) Soong programmed her with a long life and wanted her to die thinking she's human.
Data's friends support his difficult decision to leave her with that comfortable belief.
Better hope Soong does better work than Roger Corby did back in 'What Are Little Girls Made Of?'
"Inheritance" has some deeply illogical flaws, but works well emotionally. Still, I feel like Data tells his mom a terribly unnecessary lie for the sake of compassion. If the truth was out, Juliana wouldn't need to die, right? Why deny her the benefits of a lengthy android life? Also, nobody better tell Pran: the new husband's not an A.I. fan. If you tell your man: 'But I'm an android!' and his answer isn't to shrug and say 'Nobody's perfect'... maybe you're better off without him.