"So much has happened..." Phoebe trailed off, taking a deep breath. "But I guess the thing that's most important is Paige. Do you remember mom's Whitelighter, Sam?" She figured Prue would. They'd met him at the camp where their mother had died, which had been a rough time for all three of them. She kept her arm around Prue as she nodded, then continued.
"Well...mom had an affair with him, and became pregnant. She gave the baby up for adoption, and...well, Paige is our half sister. She's younger than me, and she kept her last name, Matthews." Phoebe pulled back slightly so she could watch her sister's face to see how she was coping with the news. "After you...were gone, Piper tried everything she could to get you back. Her spells ended up getting us to notice Paige and she...became one of the Charmed Ones." She suddenly realized how that might sound, and spoke up quickly. "Not that she was a replacement for you, at all. No one could ever replace you, Prue."