Syed Farook's Sister Shocked by His Wife's Alleged ISIS Support

— -- The older sister of Syed Farook, one of the suspected shooters in Wednesday’s deadly San Bernardino rampage, called reports of her sister-in-law pledging allegiance to ISIS "shocking."

Tashfeen Malik, using an alias on social media, pledged her allegiance to Abu Bakr al-Baghdadi, the head of the Islamic state, in the hours before the massacre, sources tell ABC News.

Saira Khan, Farook's sister and Malik's sister-in-law, told ABC News today, "I don’t even know who that is."

“I have no idea who she is pledging allegiance to," Khan said. "She’s never mentioned any political thing."

Khan said she and her husband, Farhan Khan, hope to adopt the 6-month-old baby girl her brother and his wife -- killed by police in a shootout -- left behind.

“At least she’ll have a stable upbringing” Saira Khan said. "We want her to enjoy her innocence."

Malik, 29, who is from Pakistan but had lived in Saudi Arabia, came to the U.S. last summer on a “fiancé” visa and later obtained a Green Card, U.S. officials have said. Malik married Farook, an American of Pakistani descent, in August 2014 and the couple had a baby daughter six months ago.

Saira Khan and her husband told ABC News that Farook and Malik were a happy couple, but private.

Saira Khan called the shooting "horrific," and to the victims, she said, "We can’t begin to imagine what they’re going through."

"We feel for them," she said.

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