Disclaimer: I do not own Harry Potter.
By Silver Sailor Ganymede
James Sirius Potter was, in Severus' opinion, the most aptly named child on the planet. He was as rowdy and loud and arrogant as both of his namesakes combined. The boy was a Gryffindor through and through and the most horrific child Severus had ever had the displeasure of setting eyes on, exactly what he would have expected from a Potter.
That was why it had been rather a shock when Severus first met Albus Severus Potter. He had heard of the boy in passing and decided to go and see whether Harry Potter's second spawn was wreaking as much havoc on the school as the first; what Hell it would have been to have an awful brat named after oneself! Luckily the boy was no Gryffindor; he was as much a Slytherin as Severus himself, always a book in his hand and an idea in his head, thinking up new ways to prove to the world that he was something more than just Harry Potter's son. He had Lily's brains and Lily's charm, and even his dark hair wasn't like a Potter's; it was tamer than his father's or grandfather's had ever been. The boy reminded Severus a little too much of himself at that age, only happier.
The shock had only intensified when Severus saw Potter's youngest child and only daughter. Her hair was long and red but not like a Weasley's; it was darker, almost auburn, just like Lily's had been. In fact she looked almost exactly like Lily had at that age. The only difference was her eyes – they were dark, not brown like Ginny Weasley's but almost black. The most surprising thing, however, was that the girl was a Ravenclaw through and through, just like he'd always thought his Lily should have been (she was smart and kind and intelligent, not brash and horrible and inconsiderate like a Gryffindor. She should never have been a Gryffindor. Not his Lily.)
When Severus looked at Albus Severus and Lily Luna, he didn't see the spawn of Harry Potter, the scions of the line of the obnoxious James Potter. No, when Severus saw those two children, his and Lily's namesakes, he saw the son and daughter that he and Lily should have had – he saw once again everything that he had lost, and even in death he could feel his heart breaking.